Maximum bullet speed: types of weapons, important factors, barrel length and ballistic coefficients

Bullets are different. Their type depends on the weapon for which they are made. There are shells for smooth-bore, rifled, and pneumatic weapons. Accordingly, they look different. The size will be determined by the type and size of the weapon.

There are large live cartridges, large bullets or very small ones for pistols and revolvers.

However, the speed of a bullet will be determined not only by its size. It is also influenced by many other factors.

Factors affecting bullet speed

A number of reasons can slow down the muzzle velocity of a projectile when fired from a weapon. Let's look at the main ones.

1. Ambient temperature. The lower the air temperature, the more energy is spent on heating the gunpowder and ejecting the projectile, that is, the initial ejection speed decreases.
2. Humidity of gunpowder. The drier the gunpowder, the higher the initial velocity will be, as the pressure in the barrel of the weapon will increase.
3. Shape and size of grains of gunpowder. The finer the dispersed particles of the powder charge, the faster they will burn. Consequently, the initial speed of the bullet will increase.
4. Powder charge density. In order to load a product with gunpowder as correctly and safely as possible, special precise engineering calculations are required. Without them, an overdose of gunpowder is possible, which will lead to internal detonation of the weapon. Or, on the contrary, underloading, which will lead to overheating of the weapon barrel. It is prohibited to independently reload the powder component in the weapon!
5. Weapon barrel length. The shorter the barrel, the less time the action of the powder gases takes place, which reduces the speed of the bullet.
6. Product weight. The lighter the bullet in mass, the higher its initial speed.

Each of these factors may vary slightly depending on the specific type of weapon. However, in general, it is these conditions that affect the initial and overall speed of the bullet when fired.

Muzzle velocity: influencing factors

For a shooter, the initial velocity of a bullet (projectile) is perhaps the most important of all quantities considered in internal ballistics.

And indeed, the greatest firing range, the range of a direct shot, depends on this value, i.e. the greatest range of direct fire at visible targets, at which the height of the bullet’s flight path does not exceed the height of the target, the time of movement of the bullet (projectile) to the target, the impact effect projectile on target and other indicators.

That is why it is necessary to be attentive to the very concept of initial velocity, to the methods of determining it, to how the initial velocity changes when the parameters of internal ballistics change and when shooting conditions change.

When fired from a small weapon, a bullet begins to move faster and faster along the barrel under the influence of powder gases, reaching its maximum speed a few centimeters from the muzzle. Then, moving by inertia and encountering air resistance, the bullet begins to lose its speed. Consequently, the speed of the bullet changes all the time. Taking this circumstance into account, it is customary to record the speed of a bullet only in certain phases of its movement. Usually the speed of the bullet is recorded as it leaves the barrel.

The speed of the bullet at the muzzle of the barrel at the moment it leaves the barrel is called the initial speed.

The initial speed is taken to be a conditional speed, which is slightly greater than the muzzle and less than the maximum. It is measured by the distance that a bullet could travel in 1 second after leaving the barrel, if neither air resistance nor its gravity acted on it. Since the speed of a bullet at some distance from the muzzle differs little from the speed when it leaves the barrel, in practical calculations it is usually assumed that the bullet has the highest speed at the moment it leaves the barrel, i.e., that the initial speed of the bullet is the highest ( maximum) speed.

The initial speed is determined experimentally with subsequent calculations. The magnitude of the muzzle velocity is indicated in the shooting tables and in the combat characteristics of the weapon.

So, when firing from a 7.62-mm repeating rifle of the Mosin system mod. 1891/30 the initial speed of a light bullet is 865 m/sec, and that of a heavy bullet is 800 m/sec. When firing from a 5.6-mm small-caliber TOZ-8 rifle, the initial bullet speed of various batches of cartridges ranges from 280-350 m/sec.

The magnitude of the initial velocity is one of the most important characteristics not only of cartridges, but also of the combat properties of weapons. However, it is impossible to judge the ballistic properties of a weapon by the initial bullet velocity alone. As the initial speed increases, the bullet's flight range, direct shot range, lethal and penetrating effect of the bullet increases, and the influence of external conditions on its flight decreases.

The magnitude of the muzzle velocity depends on the length of the weapon barrel; bullet mass; mass, temperature and humidity of the cartridge powder charge, shape and size of the powder grains and loading density.

The longer the barrel of a small weapon, the longer the time the bullet is exposed to powder gases and the higher the initial velocity of the bullet.

It is also necessary to consider the muzzle velocity of the bullet in combination with its mass. It is very important to know how much energy a bullet has, what work it can do.

It is known from physics that the energy of a moving body depends on its mass and speed of movement. Therefore, the greater the mass of the bullet and the speed of its movement, the greater the kinetic energy of the bullet. With a constant barrel length and constant mass of the powder charge, the smaller the mass of the bullet, the greater the initial velocity. An increase in the mass of the powder charge leads to an increase in the amount of powder gases, and consequently to an increase in the maximum pressure in the barrel bore and an increase in the initial velocity of the bullet. The greater the mass of the powder charge, the greater the maximum pressure and initial velocity of the bullet.

The length of the barrel and the mass of the powder charge increase when designing small arms to the most rational sizes.

As the temperature of the powder charge increases, the burning rate of the powder increases, and therefore the maximum pressure and muzzle velocity of the bullet increase. As the charge temperature decreases, the initial speed decreases. An increase (decrease) in the initial speed causes an increase (decrease) in the range of the bullet. In this regard, when shooting, it is necessary to take into account range corrections for the temperature of the air and charge (the temperature of the charge is approximately equal to the air temperature).

As the humidity of the powder charge increases, its burning rate and the initial velocity of the bullet decrease.

The shape and size of the gunpowder have a significant impact on the burning rate of the powder charge, and therefore on the initial speed of the bullet. They are selected accordingly when designing weapons.

Loading density is the ratio of the mass of the charge to the volume of the cartridge case with the bullet inserted (charge combustion chamber). When the bullet is seated very deeply, the loading density increases significantly, which can lead to a sharp surge in pressure when fired and, as a result, to rupture of the barrel, so such cartridges cannot be used for shooting. As the loading density decreases (increases), the initial bullet speed increases (decreases).

Table 1 Penetrating effect of a light bullet of a 7.62-mm sniper repeating rifle of the Mosin system mod. 1891/30 (when shooting at distances up to 100 m)
Material	Bullet penetration, cm
Steel plate	0,6
Iron plate	1,2
Layer of gravel or crushed stone	10-12
Brickwork	15-20
Pine boards (2.5 cm each), placed at 2.5 cm intervals	35 boards
Wood at the end	up to 150
Oak wood wall	70
Layer of soft clay	70-80
Earth	60-70
Layer of compacted snow	up to 350

The penetrating effect of a bullet (Tables 1 and 2) is characterized by its kinetic energy (living force). The kinetic energy imparted to the bullet by the powder gases at the moment it leaves the barrel is called muzzle energy. Bullet energy is measured in joules.

Rifle bullets have enormous kinetic energy. Thus, the muzzle energy of a light bullet when fired from a rifle of the 1891/30 model. equal to 3600 J. How great the energy of a bullet is can be seen from the following: to obtain such energy in such a short period of time (not by shooting), a machine with a power of 3000 hp would be required. With.

From all that has been said, it is clear what great practical significance a high initial velocity and the muzzle energy of a bullet, which depends on it, have for shooting. With an increase in the initial speed of the bullet and its muzzle energy, the firing range increases; the bullet trajectory becomes more sloping; the influence of external conditions on the flight of a bullet is significantly reduced; the bullet's penetration effect increases.

At the same time, the magnitude of the initial velocity of the bullet (projectile) is greatly influenced by the wear of the barrel bore. During operation, the barrel of a weapon is subject to significant wear. This is facilitated by a number of reasons of a mechanical, thermal, gas-dynamic and chemical nature.

First of all, when a bullet passes through the bore, due to high friction forces, it rounds the corners of the rifling fields and abrades the inner walls of the bore. In addition, particles of powder gases moving at high speed strike with force the walls of the barrel bore, causing so-called hardening on their surface. This phenomenon consists in the fact that the surface of the bore is covered with a thin crust with fragility gradually developing in it. The elastic deformation of the barrel expansion that occurs during a shot leads to the appearance of small cracks on the inner surface of the metal. The formation of such cracks is also facilitated by the high temperature of the powder gases, which, due to their very short action, cause partial melting of the surface of the barrel bore. Large stresses arise in the heated layer of metal, which ultimately lead to the appearance and enlargement of these small cracks. The increased fragility of the surface layer of the metal and the presence of cracks on it lead to the fact that the bullet, when passing through the bore, produces metal chips in places of cracks. The wear of the barrel is greatly contributed to by the soot remaining in the bore after the shot. It represents the remains of combustion of the primer composition and gunpowder, as well as metal scraped from the bullet or melted from it, pieces of the cartridge case torn off by gases, etc.

The salts present in soot have the property of absorbing moisture from the air, dissolving in it and forming solutions, which, when reacting with the metal, lead to its corrosion (rusting), the appearance of first a rash and then cavities in the barrel bore. All these factors lead to changes and destruction of the surface of the barrel bore, which entails an increase in its caliber, especially at the bullet entrance, and, naturally, a decrease in its overall strength. Therefore, the noted change in parameters when the barrel wears leads to a decrease in the initial speed of the bullet (projectile), as well as to a sharp deterioration in the weapon’s combat, i.e., to the loss of its ballistic qualities.

If in the time of Peter I the initial flight speed of the cannonball reached 200 meters per second, then modern artillery shells fly much faster. The flight speed of a modern projectile in the first second is usually 800-900 meters, and some projectiles fly even faster - at a speed of 1000 or more meters per second. This speed is so high that the projectile, when it flies, is not even visible. Consequently, a modern projectile travels at a speed 40 times the speed of a courier train and 8 times the speed of an airplane.

However, here we are talking about ordinary passenger aircraft and artillery shells flying at average speed.

If we take for comparison, on the one hand, the “slowest” projectile, and on the other, a modern jet aircraft, then the difference will not be so great, and not in favor of the projectile: jet aircraft fly at an average speed of about 900 kilometers per hour , that is, about 250 meters per second, and a very “slow” projectile, for example, a projectile from the 152-mm Msta 2 S19 self-propelled howitzer, with the smallest charge, flies only 238 meters in the first second.

It turns out that the jet aircraft will not only keep up with such a projectile, but will also outrun it.

A passenger plane flies about 900 kilometers in an hour. How far will a projectile flying several times faster than an airplane fly in an hour? It would seem that the projectile should fly about 4,000 kilometers in an hour.

In fact, however, the entire flight of an artillery shell usually lasts less than a minute, the shell flies 15-20 kilometers and only for some guns more.

Table 2 Penetrating effect of a bullet from a 5.6-mm small-caliber rifle TOZ-8 (when fired at a distance of up to 25 m)
Material	Bullet penetration, cm
Sheet iron	0,2
Brickwork	2,0
Pine boards	8,0
Plywood	3,2
Dry oak	3,0
Layer of soft clay	8,0

What's the matter? What prevents a projectile from flying as long and as far as an airplane flies?

The plane flies for a long time because the propeller pulls or the jet engine pushes it forward all the time. The engine runs for several hours in a row until there is enough fuel. Therefore, the plane can fly continuously for several hours in a row.

The projectile receives a push in the gun channel, and then flies on its own, no force anymore pushes it forward. From a mechanical point of view, a flying projectile will be a body moving by inertia. Such a body, mechanics teaches, must obey a very simple law: it must move rectilinearly and uniformly, unless no other force is applied to it.

Does the projectile obey this law, does it move in a straight line?

Let's imagine that a kilometer away from us there is a target, for example, an enemy machine-gun point. Let's try to aim the gun so that its barrel is pointed directly at the machine gun, then we'll fire a shot.

No matter how many times we shoot like this, we will never hit the target: each time the shell will fall to the ground and explode, having flown only 200-300 meters. If we continue our experiments, we will soon come to the following conclusion: in order to hit, we need to point the barrel not at the target, but slightly above it.

It turns out that the projectile does not fly forward in a straight line: it descends in flight. What's the matter? Why does the projectile not fly straight? What force pulls the projectile down?

Artillery scientists of the late 16th and early 17th centuries explained this phenomenon this way: a projectile flying obliquely upward loses strength, like a man climbing a steep mountain. And when the projectile finally loses its power, it will stop for a moment in the air, and then fall down like a stone. The path of a projectile in the air seemed to artillerymen of the 16th century to be as shown in the figure.

Nowadays, all people who have studied physics, knowing the laws discovered by Galileo and Newton, will give a more correct answer: the force of gravity acts on a flying projectile and causes it to fall during its flight. After all, everyone knows that a thrown stone does not fly straight, but describes a curve and, having flown a short distance, falls to the ground. All other things being equal, the stone flies farther, the harder it is thrown, the greater the speed it received at the moment of the throw.

Let's put a weapon in the place of the person throwing the stone, and replace the stone with a projectile; like any flying body, the projectile will be attracted to the ground during flight and, therefore, will move away from the line along which it was thrown; in artillery this line is called the throwing line, and the angle between this line and the horizon of the gun is the throwing angle.

If we assume that the projectile is only affected by gravity during its flight, then under the influence of this force in the first second of flight the projectile will drop approximately 5 meters (more precisely, 4.9 meters), in the second - almost 15 meters (more precisely, by 14.7 meters) and in each subsequent second the falling speed will increase by almost 10 meters per second (more precisely, by 9.8 meters per second). This is the law of free fall of bodies discovered by Galileo.

That’s why the projectile’s flight line—the trajectory—is not straight, but exactly the same as for a thrown stone, similar to an arc.

In addition, one may wonder: is there a connection between the throwing angle and the distance that the projectile flies?

Let's try to fire the gun once with the barrel in a horizontal position, another time with the barrel at a throwing angle of 3 degrees, and a third time with a throwing angle of 6 degrees.

In the first second of flight, the projectile must move down 5 meters from the throwing line. This means that if the gun barrel lies on a machine 1 meter high from the ground and is directed horizontally, then the projectile will have nowhere to go down and will hit the ground before the first second of flight has elapsed. Calculations show that within 6 tenths of a second the projectile will hit the ground.

A projectile thrown at a speed of 600-700 meters per second, with the barrel in a horizontal position, will fly only 300 meters before falling to the ground. Now let's fire a shot at a throwing angle of 3 degrees.

The throwing line will no longer go horizontally, but at an angle of 3 degrees to the horizon.

According to our calculations, a projectile fired at a speed of 600 meters per second should have risen to a height of 30 meters in a second, but gravity will take away 5 meters of rise from it, and in fact the projectile will be at a height of 25 meters above the ground. After 2 seconds, the projectile, if there were no gravity, would have risen to a height of 60 meters, but in fact, gravity will take away another 15 meters in the second second of flight, but only 20 meters. By the end of the second second, the projectile will be at a height of 40 meters. If we continue the calculations, they will show that already at the fourth second the projectile will not only stop rising, but will begin to fall lower and lower. And by the end of the sixth second, having flown 3600 meters, the projectile will fall to the ground.

The calculations for a shot at a throwing angle of 6 degrees are similar to those we just did, but the calculations will take much longer: the projectile will fly for 12 seconds and fly 7200 meters.

Thus, we realized that the greater the throwing angle, the further the projectile flies. But there is a limit to this increase in range: the projectile flies the furthest if it is thrown at an angle of 45 degrees. If you further increase the throwing angle, the projectile will climb higher and higher, but it will fall closer and closer.

It goes without saying that the flight range will depend not only on the throwing angle, but also on the speed: the greater the initial speed of the projectile, the further it will fall, all other things being equal.

For example, if you throw a projectile at an angle of 6 degrees with a speed of not 600, but 170 meters per second, then it will fly not 7200 meters, but only 570.

Consequently, the actual maximum initial velocity of a projectile, which can be achieved in a classic artillery gun, fundamentally cannot exceed the value of 2500-3000 m/s, and the actual firing range does not exceed several tens of kilometers. This is the peculiarity of artillery barrel systems (including small arms), realizing which humanity, in the quest for cosmic speeds and ranges, turned to the use of the reactive principle of propulsion.

Sergey Monetchikov Photo by Vladimir Nikolaychuk and from the author’s archive Bratishka 08-2009

What is a chronograph?

A chronograph is a special device that allows you to monitor some indicators of the internal and external structure of a projectile and, based on the data obtained, draw a conclusion about its possible speed.

The device is designed in such a way that it can be used to easily check the declared technical characteristics of a weapon in a store. In addition, it determines the initial and overall speed of the bullet.

Using a chronograph, you can view and evaluate the following weapon indicators:

• cylindrical pressure (its level);
• spring fatigue or leaded barrel;
• the device will show the mass of the cartridge;
• will evaluate the quality;
• will show wear of the piston cuff;
• temperature.

The electronic device, through calculations and generalization, will produce real results for all indicators. However, it also has its drawbacks.

Is it possible to safely catch a bullet in the air by hand after firing a weapon?

Is catching a bullet as it flies through the air an old, well-worn tale, an illusion or true?
Is this only possible in the cinema or in the circus, where magicians have long mastered this trick that deceives the audience? Can this be done in real life? Surprisingly, it's true. This is hard to believe, but at least theoretically it is possible. In order to understand whether this is possible, you need to turn to physics. see also

If a helicopter hovers in the air, will it end up on the other side of the Earth in 12 hours?
For example, imagine that you are firing a pistol upward. The bullet that leaves the barrel after you pull the trigger will sooner or later reach its maximum possible height. And the more the bullet approaches its maximum height, the lower its speed will be. At maximum altitude, the bullet's speed can be only a few meters per second. If you are in the right place at the right time, you can catch a bullet flying in the air. For example, going up in a hot air balloon.

The height, of course, will depend on the weapon and bullet. For example, to catch a bullet fired from an AK-47 assault rifle (Kalashnikov assault rifle, 7.62 caliber), you will have to climb to a height of 2.1 kilometers.

I wonder, what about the rotation of the bullet? After all, even though a bullet at a high altitude has lost its vertical momentum, the rotation set by the rifled barrel of a weapon is unlikely to stop. Yes it is. Most likely, a bullet that has lost speed at high altitude will still spin. According to the laws of physics, the bullet will not lose rotational momentum. But catching a bullet from a balloon is theoretically possible. It's just that in this case you have to grab it tightly, otherwise it will break out of your hands due to the rotation.

see also

Why a passenger plane hung in the air near Moscow: video

If you don't have a balloon, you could theoretically catch a bullet while standing at the edge of a high cliff.

But this is all theory. Have there been any cases in real life when people caught a bullet? If you believe history, then such cases have happened in our sometimes strange and wonderful world, where, apparently, everything is possible.

One of the classic options was described in the book of the popularizer of the exact sciences and the founder of the popular science genre of “entertaining science” Yakov Isidorovich Perelman, “Entertaining Physics” - when a pilot during the First World War managed to catch a bullet literally with his bare hands:

“During the First World War, as newspapers reported, a completely unusual incident happened to a French pilot. Flying at an altitude of two kilometers, the pilot noticed that some small object was moving near his face. Thinking that it was an insect, the pilot quickly grabbed it with his hand. Imagine the pilot’s amazement when it turned out that he had caught… a German live bullet!”

On the one hand, this seems like an impossible story, but, again, all sorts of miracles can happen during a battle. As they say, everything you can imagine is possible, and in the rapidly changing kaleidoscope of battle events, such a chance will be increased many times in proportion to the number of those very events.

The explanation of the phenomenon is easily and accessiblely given in the following paragraph:

“The bullet does not always move at its initial speed of 800-900 m per second. Due to air resistance, it gradually slows down its flight and by the end of the journey - at the end - it makes only a few tens of meters per second. And the same speed can be achieved by an airplane. This means that it can easily happen that the bullet and the plane will have the same speed: in relation to the pilot, the bullet will be stationary or will move barely noticeably.”

Thus, the answer is given under what conditions a pilot can see the flight of a bullet with his own eyes and literally catch it.

Reasonable! But entertaining physics is much more multifaceted than just one historical example. There are many different options you can come up with. For example, it is worth assuming several options with the same bullet and a fast-moving vehicle, say a train, or even better - with the same plane.

Fortunately, now the fastest trains can travel quite at the speed of a pistol bullet in the average values ​​of its movement after a shot (not the initial speed of the bullet, remember the loss of kinetic energy during friction with the airspace).

For example, the fastest maglev (magnetic levitation train) reached a speed of 603 km/h during railway tests in 2015:

Literally moves at the speed of a bullet.

Well, we are generally silent about airplanes, especially military ones, fighters and attack aircraft.

Therefore, there can be many situations, for example: we are flying on an airplane at a speed of 1,000 km/h, say, in a western direction. The initial speed of the bullet is also 1,000 km/h. How fast will the bullet travel when fired?

The relativistic law of addition of velocities will operate here: V=(v1+v2)/(1+v1v2/c^2) (in which V is the speed of the body relative to the fixed coordinate system, v1 is the speed of the body in the moving coordinate system, v2 is the speed of this mobile system relative to the stationary one). The formula for finding speed is a little more complex than according to the classical law of adding speeds V=V1+V2 .

It would seem that the answer is obvious and known even to schoolchildren: relative to us, the bullet will fly at a speed of 1,000 km/h. But this is precisely relative to us, already moving at a speed of 1 thousand kilometers per hour, that is, from our reference system. However, the indicators will be completely different if we take a different frame of reference as a basis.

You've probably heard of Newton's first law:

“Every material body maintains a state of rest or uniform rectilinear motion until the influence of other bodies forces it to change this state.”

Thus, if we imagine an ideal vacuum in which nothing would interfere with the flight of a bullet and the straight-line movement of an aircraft, a bullet fired at a speed of 1,000 km per hour will always move away from the place of the shot at a given speed. That is, the projectile will move away from the plane at a speed of 1 thousand kilometers per hour, just as if the plane was standing motionless on the ground.

see also

This is why we don't use gunpowder to power cars.

However, since the plane is moving in space, their speeds will add up, which means that relative to the Earth the bullet will fly at a speed of 2,000 km/h. For a stationary observer located in a different frame of reference, the bullet will move exactly at this speed.

Disadvantages of a chronograph

The device has a certain weight and size, which makes it not always convenient to use in certain conditions (for example, field). Another disadvantage of this device is the measurement error (electronic). It is not too significant, but it still takes place.

The device counter starts and stops depending on the illumination of the area (room), which also creates a certain error in the readings.

Such a device will not reliably show the exact real trajectory of the bullet; for this, another measurement method should be used.

What's wrong with speeds?

Here are just a few very recent examples of this kind.

The German “Diana”, famous for its conservatism, in the “Catalogue 2017” for new rifles of the “magnum” class (25x100 mm compressor) equipped with high-pressure gas springs “N-TEC”, gives speed characteristics of 400 meters per second (see “ Air rifles "Diana" on my website arbalet-airgun.ru ).

At the same time, the Germans left the classic, albeit also overestimated, speed of 380 m/s for their famous “supermagnum” 350 series. Well, okay, let gas springs have some “magical” properties, although in reality they do not differ in force from their steel counterparts. But for the newest “super” “Diana Panther 350 N-TEC” (29x120 mm) with a much more powerful scramjet engine, the same 400 m/s was indicated.

How this happened is unclear, because this is all nothing more than elementary arithmetic...

The largest European arms manufacturer simply increased the speed characteristics for all its models. Thus, the ancestor of most magnums, the Hunter 440, for no apparent reason suddenly “shot” at speeds of 386 m/s, although last year it was “content” with the slightly inflated advertising, but still more modest 305 m/s. And the most powerful “supermagnums” in the world, “Hunter 1250 Grizzly IGT Mach1” and “G-MAGNUM 1250 IGT” (pictured), which have just appeared in the production line, according to the “Catalog 2017”, produce 47 0 m/s! (see “Gamo air rifles” on the website arbalet-airgun.ru )

Such a pursuit of sales growth for such eminent manufacturers looks somehow undignified. At the same time, the legendary “Hatsan”, all of whose products were initially more powerful than Dian’s analogues, did not get carried away with science fiction and retained the same characteristics for its products. His example is followed by the equally famous Stoeger and Crosman. How is everything going in reality?

Here are the real speed indicators for the main classes of 177 caliber (4.5 mm) spring-piston rifles and the main types of bullets:

• for “magnum”, 20 joules: “half a gram” (0.55 g) - up to 280 m/s, “heavy” (0.68 g) - 240 m/s. “Hatsans” (25 J) - up to 300 m/s with light bullets (which is already undesirable) and 270 with heavy ones.
• for “supermagnum”, 29-33 joules: “heavy”, they are also the minimum permissible (0.68 g) - 290-310 m/s.

On my three magnums (Diana 31, Gamo Socom Carbine Luxe, Hatsan Striker) and one super (Hatsan mod 135), the speeds also quite corresponded to them. Where did all these fantastic numbers of 380-400-470 m/s m/s come from? The secret is in using ultra-light bullets for advertising purposes, which are not at all designed for such power, but are very fast.

Pre-charged pneumatics (PCP) are no exception. It is clear that by pushing an ultra-light bullet into the drum and working hard with the pump, you can achieve speeds exceeding 400 meters per second, almost at the level of a smooth-bore firearm. However, PCP owners use ammunition that is suitable specifically for their weapon and optimize the pressure (the so-called “plateau”) or set the gearbox to optimal values. Depending on the caliber, the weapon produces from 220 to approximately 320 m/s, and the more powerful it is, the lower the speeds, and the heavier the bullets! In addition, the silencers installed on most modern PCP rifles, like those on firearms, work correctly only at subsonic (up to 330 m/s) speeds.

For hunting, the main thing is the stopping effect of the projectile. That is, with light high-speed bullets it’s good to pierce boards on a dare, but heavy bullets will get stuck in them, transferring all the destructive energy to the mass of the tree. The same is true of living flesh.

In principle, this could have ended here - the truth has been voiced, the culprits have been named. But if you really want to understand the essence of the issue, and most importantly, decide on the characteristics of your particular rifle and select the optimal ammunition for it, then you should continue reading this article. It will be interesting - then I will give examples of calculations of real indicators of air guns.

Shooting at various distances

This is a more accurate and realistic way to determine the speed of a bullet. To do this, you will need not only attentiveness, but also a computer with a ballistic calculator installed, which will provide complete information and the most accurate calculations.

The work proceeds according to the following scheme:

• we load the necessary data into the ballistic calculator, which we take from the weapon manufacturer and from the indicators obtained with our own hands (we shoot the weapon to zero at 100 m);
• enter the mass of the cartridge, the shooting distance;
• measure and load the height of the sight above the weapon barrel;
• We take data from the manufacturer about vertical and horizontal clicks in the optics;
• We enter the temperature and air pressure readings at the time of the study (the more accurate, the more real and better the result will be);
• altitude indicator;
• bullet speed from the manufacturer.

The calculator will have graphs for shooting distances. There we indicate 200, 300, 500 and 700 meters. Longer distances are not immediately recommended. In the columns where 1MOA is requested, we write the following values ​​according to the order of distances: 5.8; 8.7; 14.5; 20.3 centimeters.

All the rest of the work is just a matter of clicking the mouse on the calculator. Follow the navigator through the ballistic device and as a result you will get an accurate and real indicator of what the speed of the bullet is.

Hypersonic cartridge: effective, but difficult

For several decades now, the development of small arms has been following the path of improving existing ideas.
Fundamentally new solutions are proposed and studied, but do not find application in practice. A new revolution may take place in the near future, providing for a serious technological breakthrough. Russian gunsmith designers announced the possibility of creating a completely new class of ammunition - the so-called. hypersonic cartridges. The result of such a project could be the emergence of weapons with uniquely high technical and combat characteristics. Loud news
At the end of September, RIA Novosti published interesting statements by Russian businessman and weapons designer Vladislav Lobaev. The chief designer of the Lobaev Arms company, known for its developments in the field of precision weapons, spoke about the possibility of creating a new ammunition with improved characteristics. Moreover, he indicated the possible timing of the appearance of such a product, although he mentioned certain conditions necessary for its development.

According to V. Lobaev, research is currently underway on the promising topic of a cartridge with a hypersonic bullet. The arms company is capable of developing such ammunition in about a year. The initial speed of his bullet can reach the level of 2000 m/s. However, to implement such plans, the Lobaev Arms company needs some support from the state.

Rifle cartridges 7.62x54 mm R. Maximum bullet speed - no more than 900 m/s

The gunsmith spoke about the purpose of promising cartridges. Such ammunition is proposed to be used with high-precision sniper weapons. The increased initial speed should ensure an increase in the range of effective fire, as well as increase armor penetration. In addition, it can be used to reduce the height of the trajectory. The new ammunition will show a speed of 2000 m/s, while most modern rifles accelerate the bullet to speeds of no more than 1200 m/s.

V. Lobaev touched upon the technological side of the new project. Modern gunpowder will not be able to transfer the required energy to the bullet. As a result, the new cartridge will have to carry a propellant charge of a detonating substance of a special composition. More accurate data on the type of charge, its weight, etc. have not yet been announced.

News about the study of hypersonic ammunition for small arms looks extremely interesting and promising. The advantages of such cartridges are obvious, and their appearance can have the most serious impact on the further development of small arms - at least sniper weapons. However, even now, in the absence of the entire volume of data on the promising project, it is clear that the development of new ammunition may encounter serious problems.

Shooting complex

Obviously, a promising hypersonic cartridge cannot be created on its own. A product with special characteristics requires a special weapon, the design of which will ensure compatibility with it. At the same time, it may turn out that developing a new sniper rifle for a special cartridge will be extremely difficult. Designers will have to solve a number of specific problems, without which it will not be possible to obtain the optimal balance of characteristics.

To ensure hypersonic bullet speed, it is necessary, first of all, to significantly increase the pressure created by the propellant charge. Increased pressure places new demands on the strength of the barrel group, which directly interacts with gases. In addition, an increase in bullet speed and energy should lead to an increase in recoil momentum - this factor affects all other elements of the weapon.

Designers will also face challenges in the field of materials science and technology. It is worth recalling that at present, an initial speed of more than 1500-1700 m/s is typical for armor-piercing sub-caliber projectiles of tank guns. Due to high speed and other factors, such ammunition gradually wears away the surface of the bore. The life of the barrel without bore protection does not exceed several hundred shots.

There is every reason to expect that a promising rifle chambered for a hypersonic cartridge will also encounter similar problems, and its barrel life will be much lower than that of similar weapons chambered for “conventional” ammunition. However, the use of modern technologies and materials can solve all difficulties. Obviously, a finished rifle of a new type will be of no less interest than the ammunition for it.

Ammunition architecture

Talking about the new project, V. Lobaev mentioned new compositions of propellant charges. However, he did not talk about abandoning traditional unitary ammunition. Apparently, the future hypersonic cartridge will be as similar in appearance to existing products as possible. The new propellant charge will be placed in a metal sleeve, at the bottom of which there will be an ignition agent. The dulce, as before, will accommodate a bullet.

What specific substance will be used to accelerate the bullet was not specified. The designer only mentioned the fact that it would be a new type of detonating chemical. Numerous new grades of propellants have been developed and tested in recent decades; in parallel, alternative substances with the desired qualities were proposed. It is unknown what exactly will be placed in the hypersonic cartridge case.

.300 Winchester Magnum cartridge. Bullet speed - up to 990-1000 m/s

It should be noted that the propellant charge must be selected according to a number of basic parameters. First of all, you need to take into account the energy of combustion and the pressure created. However, it should be remembered that an increase in pressure in the barrel, accelerating the bullet to the required speeds, is quite capable of leading to a significant change in internal ballistics. The nature of charge combustion and the passage of a bullet through the barrel with high acceleration should become topics of new research.

Thus, just to select a suitable propellant charge and determine its weight, the authors of a promising project will need to carry out several serious research projects. Scientific organizations of different directions can be involved in them. It is not at all difficult to understand why the head of the arms company spoke about the need for government assistance.

Hypersonic bullet

The speed of small arms bullets usually does not exceed 1000-1200 m/s. A new project from Lobaev Arms could result in a bullet with an initial speed of up to 2000 m/s - more than 5.8 times the speed of sound. This increase in speed leads to new requirements. The bullet must have a special design that will allow it to realize all the benefits of high speed. It will probably be possible to use existing materials and technologies in its design, but there may also be a need for new ones.

First of all, the bullet must be highly durable and resistant to mechanical and thermal stress. While in the weapon, the bullet will encounter increased acceleration, which can deform an object that is not strong enough. During flight at hypersonic speed, a shock wave, an unstable boundary layer, etc. should form around the bullet. All this can lead to additional mechanical stress.

Particular risks are associated with the freestream temperature. It is known that hypersonic aircraft heat the air around them to a temperature of several thousand degrees, depending on the nature of the flow and the configuration of the airframe. The same should be expected in the case of a bullet. Thus, it must combine mechanical strength and resistance to heat. This places special demands on the materials used.

Modern sniper rifles use ammunition with a pointed bullet of one type or another. Whether such a bullet can show the desired characteristics when accelerating to hypersonic speed is a reason for a separate study. For now, it cannot be ruled out that in order to obtain improved combat characteristics, it will be necessary to use bullets of new shapes and configurations. However, one can hardly expect that such a bullet will resemble modern hypersonic aircraft, which have a characteristic exterior.

A question of expediency

Like other promising weapons concepts, a hypersonic cartridge may have both pros and cons. The balance of expected strengths and weaknesses can pave the way for the project or lead to its abandonment. In the future, the potential customer will also have to evaluate the real capabilities of the proposed weapon, determining further actions. What will be the real balance of the pros and cons of the finished shooting complex is a big question.

The main advantages of a cartridge with a hypersonic bullet are obvious. A high-speed bullet receives more energy from gases compared to a “regular” bullet. Thanks to this, it is able to fly over a long range and have a different effect on the target. The bullet’s flight time to the target is also reduced, and its trajectory becomes flatter, which should have a positive effect on the accuracy of fire. In general, in terms of general characteristics, the hypersonic bullet from a special cartridge for advanced weapons is superior to existing models.

However, high performance comes at a price. First of all, such a cost lies in the excessive complexity of both the cartridge and the weapon for it. Increasing loads and the need to use new materials should affect the design features of the weapon. In addition, a new type of shooting system is unlikely to be cheap. It should be noted that complexity and cost can be critical. A potential customer will have to consider the cost and characteristics of the complex, and then determine whether the new capabilities justify the extra expense.

Cartridge .338 Lapua Magnum. Initial bullet speed - about 1000 m/s

However, it will be possible to evaluate only a finished project or a full-fledged cartridge, but the new concept is still at various stages. To study its real prospects, shape the technical appearance of the cartridge and rifle, as well as further development of the project, time, money and the participation of various research organizations are needed. First, it is necessary to conduct a series of studies aimed at studying the real prospects and appearance of a hypersonic cartridge.

Project of the future

According to V. Lobaev, his company is able to present a finished cartridge with a hypersonic bullet within a year - provided that the state provides the necessary support. The need for financial and organizational participation of government agencies is quite understandable: not all private arms companies are capable of carrying out complex research projects and developing fundamentally new models. If they receive the necessary support, the project has a chance.

When developing a new shooting system, engineers and scientists may encounter the most serious difficulties, which, among other things, will affect the timing of the work. It is quite possible that the statement about a new cartridge in a year will turn out to be overly optimistic. However, the Lobaev Arms company does not disclose the details of its work, and it may already have some developments on promising topics.

However, as with other breakthrough projects, the development of a new hypersonic cartridge requires the collaboration of a number of organizations capable of conducting research, creating projects and producing prototypes. Statements about the need for government support were made approximately two months ago, and since then no information about the project has appeared. Whether government agencies are interested in the bold proposal is unknown.

In recent years, there has been an active development of cartridges for small arms, but fundamentally new products using non-standard concepts have not yet been able to reach operation. Russian small arms developers have already taken up the new topic of the so-called. hypersonic cartridge and are ready to begin developing such a product. Whether they will be able to solve such a difficult problem will become known later. We will wait for new reports on the progress of work and news about the appearance of a fundamentally new ammunition.

Based on materials from the sites: https://ria.ru/ https://rg.ru/ https://vpk-news.ru/ https://modernfirearms.net/ https://armor.kiev.ua/

Some speed values ​​for cartridges of different calibers for an assault rifle

As mentioned above, it is difficult to give an accurate assessment of such an indicator as speed. It is largely determined by surrounding circumstances. However, approximate values ​​for different caliber machine gun bullets can be given.

Research and calculations have shown that the flight speed of a cartridge from an assault rifle will depend on its model and caliber, so variations in the given data are possible. But these errors are small, and everyone can correct them for their weapon themselves.

And the bullet is full of holes!!!

This is what the orthodox artillery experts will say after reading this article, and they will be right - indeed, the bullet turned out to be full of holes. But this is not on purpose, the immutable laws of physics ordered it this way. Let me make a reservation right away that the author has nothing to do with the topic of small arms; one might say, he is a pacifist and Greenpeace rolled into one. The topic was of interest only because the events more than fifty years ago on the pass now called “Dyatlov Pass” clearly spoke of the use of an unknown type of weapon there. The sum of the known facts about the events at Dyatlov Pass can only be explained by assuming that nine tourists were killed by high-velocity small-diameter bullets. So, initially, interest in the topic of small arms arose from the question of how to accelerate a miniature arrow-shaped object with a diameter of about a millimeter to a speed of 10-20 km/sec. These are the characteristics that the bullet of this unknown weapon should have had.

Of course, one can assume that some exotic technology such as a railgun was used to accelerate such a miniature bullet, but I think everything is much more prosaic; the same result can be obtained using conventional gunpowder technologies available since the middle of the last century, or even earlier. These technologies were discussed in the article “The Lemon Pit Principle”, but the main question remained unexamined there - the initial launch of such a miniature bullet and the principle of its stabilization in flight.

Filling this gap, I will describe a real method of accelerating a bullet based on a technology known but never used in cannon artillery, and, moreover, I will demonstrate the implementation of this technology on a working prototype.

Artillery classic - piston acceleration of a projectile

Since the time of “Tsar Pea,” traditional shooting systems have used a piston-cylinder kinematic system. The “Tsar Cannon” and the modern artillery system are completely similar in principle of operation.

Barrel shooting technology for projectile acceleration has been used unchanged for about a thousand years and, in its kinematic essence, is a piston (projectile) - cylinder (barrel) system. Energy is transferred to this system through the combustion of gunpowder leading to a sharp increase in pressure on the bottom of the piston (projectile). Accordingly, the speed of the projectile is proportional to the area of ​​the bottom of the projectile and the pressure in the barrel; these proportions determine the limit of the acceleration speed of the projectile.

So both the unicorn of the Middle Ages and the ultra-modern art system are essentially the same thing; moreover, the slow development of technology has closed the circle, artillery began with smooth-bore weapons and ends its evolutionary development again in the smooth-bore version.

But evolution is still not a circle, but a spiral, so the idea of ​​​​an even earlier period in the development of weapons - the throwing dart - is again used. Rifle - from the word arrow, by the way. Here's a snapshot of what can be pushed to the limit from a classic barreled shooting system:

A snapshot of a real shot, a sub-caliber projectile at the moment of resetting the calibration tabs. The barrel of this rifle system is not rifled; an aerodynamic tail is used to stabilize the flight of the projectile; in fact, artillerymen have again begun to use arrows; such a core cannot be called a bullet (projectile).

Speeds of 2-2.5 km/sec are maximum even for such an improved piston projectile acceleration technology; further increases in speed are limited by the maximum pressures withstandable by the artillery barrel.

But modern civilization also has at its disposal another technology for creating high-speed kinetic weapons, which came from even more ancient times.

Aerodynamic acceleration

Don’t think that the author has “lost his mind” by posting a photo of a sailboat in an article about weapons. The sailboat (clipper) is directly related to the topic under discussion.

Humanity has been using wind energy since time immemorial, and it can be used not only for the movement of such sea monsters, but also in artillery. After all, what is an explosion in its essence?

This is a VERY, VERY strong wind.

I haven’t discovered America here; this method has already been used in artillery since the middle of the last century. A cumulative explosion has been used to disperse small objects (let’s call them “bullets”) since the beginning of the last century; this is the so-called “impact core” technology in cumulative ammunition. This is what the aerodynamic principle of “bullet” acceleration looks like in practice:

This is a photo of the impact core in flight, immediately after its departure from the gas cumulative jet (black cloud on the right), a trace of the shock wave (Mach cone) is visible on the surface.

Let's call everything by its true names, the impact core is a high-speed bullet, only accelerated not in the barrel, but in a stream of gases. And the shaped charge itself is a Barrelless artillery mount. Bullet acceleration is carried out using an aerodynamic type of energy transfer.

But this technology is also used as a self-sufficient artillery system. An example would be the development of the early 80s of the last century, the domestic anti-tank “mine” TM-83, with a destruction zone of more than 50 meters. And here is a modern, and again domestic example of such a barrelless artillery mount:

This is an anti-helicopter mine, the “spitting” range of the shaped charge is up to 180 meters. The speed of its “bullet” is 3 km/sec, it is very far from the theoretical limit of technology of 200 km/sec, but this is an inevitable price to pay for the accuracy of aiming in such a barrelless artillery system. From all of the above, an obvious engineering solution arises; it is necessary to combine barrel technology, with its aiming accuracy, and the technology of aerodynamic acceleration of a projectile with its real potential for achieving a speed of 200 km/sec.

Clipper in a bottle

There is no escape from the maritime theme; after all, the sail was invented by sailors...

If we consider the bottle as a barrel, and the model of a sailboat as a bullet, we will get the artillery system we need.

Well, the wind will create a powder charge between the bottom of the bottle and the sailboat...

With a blank shot from a conventional rifle gun, the gas outflow speed will reach 5-7 km/sec, this is no small amount and such a “breeze” is quite enough to accelerate an aerodynamic bullet. All that remains is to place a bullet with aerodynamic surfaces (sails) inside the barrel, and now the shooting mount is ready, which, to the limit, can accelerate the bullet to the speed of the gas jet.

To stabilize the flight of such an aerodynamic bullet both in the barrel and, more importantly, in the atmosphere, it is necessary to give the bullet a rotational movement, not with the help of rifling, but also by the aerodynamic method. This can be done using not primitive “straight” sails, but more cunning, “oblique” sails, the result will be approximately the following design:

This is a gas turbine rotor; the design of an aerodynamic bullet should be approximately the same. The combustion products of gunpowder, passing through the blades, will push such a bullet forward and spin around the central axis.

By the way, the efficiency (efficiency factor) of free-flying turbines (with a loose axis of rotation) approaches 80 percent, and piston systems cannot convert energy with an efficiency greater than 30 percent, as they say, feel the difference.

But that’s not all, while moving in the barrel, the aerodynamic bullet should not touch the walls of the barrel, otherwise neither the barrel nor the bullet will remain intact, you need to ensure a uniform gap between the walls of the barrel and the ends of the sail surfaces, and the smaller it is, the better.

This technical problem has already been solved in completely different fields of technology; the air cushion method in an aerodynamically profiled gap between two planes is already used in aviation (ekranoplanes) and in computer technology (hard drives).

The magnetic heads of the hard drive “float” above the surface of the disk at a distance of several microns; the air cushion is created by the turbulent air flow from the rapidly rotating disk. For an aerodynamic bullet, microns are too much; a gap of 0.1-0.2 millimeters is enough, which is much easier to ensure.

In fact, not only the plane of the “sail”, but also its end will act as an aerodynamic surface of the bullet. Aerodynamicists know very well what shape it should be to ensure self-centering in the barrel bore.

Here is such a “holey” bullet looming, and this is not at all a traditional lead blank, used since the time of “Tsar Pea” in almost unchanged form, it is a product of advanced achievements of at least two scientific disciplines, gas dynamics and aerodynamics. It's a small matter, all that remains is to make such an aerodynamic bullet.

And “I made it...”

Of course, I am far from the English masters with their small scope, even though I am Russian, I am completely Left-handed. He acted in the traditional way for a Russian peasant, as in the joke - with the help of an angle grinder, pliers and some kind of mother...

Aerodynamic bullets in their most primitive but workable form are made from an ordinary self-tapping screw with a diameter of 4.5 mm and a length of 7.5 millimeters. Accordingly, to shoot such holey bullets, an air rifle with a barrel diameter of 4.5 mm is used. For now, this will be enough to test the effectiveness of the method of aerodynamic acceleration of a bullet.

So in the picture you see the world’s first aerodynamic bullets (or not the first?):

The threads act as aerodynamic planes, and at the same time they spin the bullet around the axis of movement using the “oblique sail” effect. Air can pass freely along the thread (three full turns of the thread) and between the thread and the walls of the barrel (the actual diameter of such a “holey” bullet is 4.4 mm). The window for free passage of air is a quarter of the cross-section of the barrel, the bullet turned out to be really full of holes.

Naturally, such a bullet has no balancing, a mock-up, what can you get from it... But theoretically, such a “holey” bullet should fly much better than a standard lead bullet. All that remained was to test the theory in practice, so it was time for experimental shooting.

“And experience, the son of difficult mistakes and .....”

Out of modesty, I will not continue the quote further.

Experimental shootings were carried out with this air gun; it is not a rifle, its barrel is not rifled.

Crosman Recruit RCT525X

The choice of weapon was not accidental; I was looking for such a smooth-bore contraption on purpose. A rifled barrel for an aerodynamic bullet is absolutely unnecessary and, moreover, harmful. The low speed of the bullet and the lack of balancing in the layout leads to its yaw in the barrel and it, clinging to the rifling of the barrel, begins to tumble in flight. This has been tested experimentally, hence the title of this section of the article.

In addition, this gun is a pump-action type and the force of the shot depends on the number of “pumps” of the pump, so you can check the effectiveness of aerodynamic bullets on different volumes of gas charge.

Here are photographs of shooting on a 1.2mm thick aluminum sheet, the rifle was inflated in both cases to seven “pumps”, this is about a third of the maximum power of this weapon. On the left is a standard lead bullet weighing 0.51 grams, on the right is an aerodynamic bullet:

As you can see, an ordinary bullet did not have enough energy to pierce the aluminum sheet, but an aerodynamic bullet pierced the sheet right through. Comments, as they say, are unnecessary.

Obviously, if a craft made literally on the knees surpasses in its characteristics factory products with centuries-old technology, then this is very serious. If such an aerodynamic bullet is made in the factory, with calculated configuration parameters, balanced, and a specially profiled barrel is made for firing it, then the result will be even more impressive.

And this will be done, so in terms of aerodynamic bullets for pneumatics there will be a continuation, the main thing will be the study of shooting accuracy, there are good reasons to assume that in this too the “holey” bullet will surpass the classic “piston” bullets.

But pneumatics is only a test of an idea, and if even at this primitive level a significant positive effect is achieved, what will happen if this technology is applied to gunpowder shooting systems?

The result will be exactly the same bullets that were used to kill tourists at the Dyatlov Pass back in 1959...

But from this place, please, in more detail...

You don’t have to be an alien to make such an aerodynamic bullet; it could well have appeared in the last century, for example in Germany during the Second World War.

It was in Germany in the mid-30s of the last century that the principle of a cumulative explosion was discovered and the impact core method was first used. Combining these technologies with barreled rifle systems is an obvious idea.

The simplest solution would be to place an aerodynamic bullet in a regular unitary cartridge; in this case, you can count on a speed limit of about 10 km/sec. This limit is determined by the burning rate of the gunpowder and the maximum pressure in the barrel. A further increase in bullet speed is only possible by replacing gunpowder with a detonating explosive.

The fundamental difference between the occurrence of a chemical reaction by the method of detonation (simultaneous chemical reaction throughout the entire volume of the explosive) and combustion (gradual chemical reaction) is the ability to focus the pressure drop wave. It is the effect of focusing the blast wave that is used in the technology of a cumulative explosion, which makes it possible to accelerate the gaseous products of an explosion to a speed of 200 km/sec. And this is what we need.

The only problem: it is impossible to explode the entire volume of the detonating substance at once. Although the barrel is not tightly plugged with a bullet, all the energy of the explosion cannot be immediately utilized without breaking the barrel.

The detonating substance must be exploded in small portions, at the moment an aerodynamic bullet flies past them. Accordingly, the design of the cartridge becomes significantly more complicated.

This is not a brass “jar” with a capsule at the bottom; you cannot do without cunning and non-obvious technologies.

Such technologies are already in use; an example is the Explosive Magnetic Generator (microwave bomb), which uses the method of controlled detonation of powerful explosives to accurately compress magnetostrictive materials that generate microwave radiation.

As a summary of all of the above, we can state that achieving a bullet speed of 10 km/sec is quite possible even in the classic version of a unitary cartridge equipped with an aerodynamic bullet. But a further increase in speed will require a completely different design of the barrel and cartridge (sleeve), in fact the sleeve will become part of the barrel. And at the same time the sleeve will turn into a very complex engineering product.

“And finally I’ll say...”, “Love us dirty, everyone will love us clean...”

That’s all for starters, I foresee a storm of angry accusations against myself and unfounded criticism of the idea of ​​​​aerodynamic acceleration of a bullet. Yes, let them say...

In the next material there will be a video of a real shooting of an aerodynamic bullet made not “on the knee”, but according to all the rules of aerodynamics, after all, I am a physicist.

Then the moment of truth will come.

AKS-74U caliber 5.45Х39 and AK-101

If we talk about the speed of a fired bullet from an AKS-74U with a 5.45X39 caliber, it will be approximately 740 m/s. Smaller than the previous one, because the barrel is shorter.

AK-101 caliber 5.56X45, on the contrary, will show a very good result in this indicator. Approximately 930 m/s, thanks to the long-barreled structure of the weapon. The American analogue of this weapon has an even longer barrel length; the same cartridges with the same initial shot velocity are suitable for both types of machine guns.

Barrel length and muzzle velocity

Photo by Andrey Talanov

True, this would require a very long barrel. In reality, you have to be content with a speed of about 400 m/s, but the barrel length is also reduced to 700-750 mm. Thus, the “efficiency factor” of a powder shot is only 30% of the total energy of the gunpowder, and 70% of the energy is spent on the sliding friction of the projectile in the barrel, on the aerodynamic resistance of the air in front of the projectile, on heat losses from the outgoing powder gases and on recoil. The last component is small - about 0.5%.

I tried to find out in what proportion these losses were distributed, but in the domestic hunting literature I did not find anything on the internal ballistics of a shotgun shot, except for the book by N.A. Izmetinsky and L.E. Mikhailov “Izhevsk Guns”, (Izhevsk, 1995), in which, by the way, this issue is also not resolved.

True, there are works on the internal ballistics of guns, for example, by I.P. Grave, N.F. Drozdova, M.E. Serebryakov and others. Unfortunately, there is no strict analytical solution to the problem of internal ballistics and, as these authors claim, there cannot be due to the complexity of the pyrodynamic processes during a shot. However, I really wanted to solve this problem at least approximately.

Finally, I came across the book “Internal Ballistics of Guns” by J. Korner (M, 1953), which gave an approximate analytical solution to this problem. According to his formulas, knowing the strength of the gunpowder and its burning rate, it was possible to find parameters such as the maximum pressure of the gunpowder, the pressure of the gunpowder at the end of combustion and their distances from the muzzle, as well as the muzzle pressure. In addition, the projectile velocities could also be found at these same points.

Unfortunately, the solution was given without taking into account the resistance forces, which did not provide a final solution. After appropriate attempts, we managed to find an acceptable technical solution. The overall energy balance is as follows: the kinetic energy of the projectile is 30%, the loss from sliding friction is 26, 20 is spent on aerodynamic drag, and 25% of the energy is lost with the heat of the powder gases.

By the way, this information is for those who are too lazy to clean their guns and shoot with ungreased wads, as well as use wads with poor sealing properties. In the latter case, the pressure in the space behind the projectile drops, and the powder gases that escape past the wad or through the wad further increase the aerodynamic drag.

And the fact that this braking is really significant, then all the external ballistics of shells, mines and bullets is only concerned with studying the influence of air resistance in open space and the acceleration of gravity on the flight of a projectile. The resistance of a projectile in a semi-closed bore increases five times.

Increasing the barrel length to some extent contributes to an increase in the muzzle velocity of the projectile only as long as the force of the powder gases exceeds the braking. But after the maximum muzzle velocity occurs, it decreases until the projectile completely stops in the barrel.

Thus, according to the book “Izhevsk Guns”, the increase in speed from 500 mm to 720 mm is only 8 m/s. A further increase in barrel length would add even less to the muzzle velocity, so a 220 mm long “supergoose” attachment would increase the lethal range of shot No. 0 by only 1.5 m. According to my calculations, with a barrel length of 8 m, the shot would not leave the barrel at all.

Now a little off topic. My hunting buddies asked me the question: “Which bullet is more effective, heavy or light?” I couldn’t answer anything right off the bat, but after some calculations the following came out. If we compare two round bullets with the same diameters of 18 mm, but different masses, 35 g and 30 g (mass ratio 1.17), whose velocities are 400 m/s and 432 m/s, respectively (so that the initial kinetic energies are equal), then at a distance of 120 m their speeds will be equal, but the kinetic energy of a 35 g bullet will naturally be higher than a 30 g bullet.

But a light bullet has a higher velocity throughout and therefore a shorter flight time and a smaller reduction in the bullet's trajectory. This reduction at a distance of 120 m for a heavy bullet is 73 cm, and for a light bullet - 68 cm. The gain is only 5 cm. For bullets of another type, if they differ only in mass, there will be different numbers, but the end result will be similar - a light bullet with each the flight meter will be inferior to a heavier bullet.

If the masses of the bullets differ to a lesser extent, then the gains and losses will be insignificant. For example, Rubeykin bullets machined from brass (density 8.6 kg/dm3) and steel (density 7.8 kg/dm3) will have a mass ratio of 1.1, so they can be considered the same, but the cost of brass is much higher . So decide for yourself which bullets to make and use!

Igor Arbuzov March 22, 2013 at 00:00

Muzzle energy of a bullet

In addition to speed, bullet energy is also a very important characteristic. To calculate muzzle energy, it is worth remembering the usual school physics course. The simplest formula will be: (mass x speed)2/2, (mass in kilograms, speed in meters per second).

Why is cartridge energy important? Because energy is the power of a bullet, its main combat characteristic. The greater the mass and the higher the speed, the correspondingly higher the energy. This means that the weapon itself is more powerful and long-range.

In other words, this is the usual formula for calculating the kinetic energy of a body. Rifle bullets have the maximum muzzle energy. They balance the mass and initial velocity of the bullet in such a way that the work is powerful and effective.

For example, at a distance of about 100 meters, the depth of penetration of a rifle bullet into fairly dense materials ranges from 0.6 to 350 cm. These are materials such as a steel plate, wood, iron plate, a layer of soft clay, gravel or crushed stone, brickwork, earth or compacted snow. These data are based on a study of the muzzle energy of light bullets by mass.

Obviously, the value of the speed and muzzle energy of any projectile is very high and determines the power and range of the weapon.

Formula for calculating energy, speed and mass of a bullet

Now we will conduct a “session of exposing black advertising magic.” To do this, we will resort to the help of the exact sciences - mathematics, physics, as well as more highly specialized ballistics (read the full version of this article and other specialized materials on the peculiarities of shooting and hunting with pneumatics on my website arbalet-airgun.ru).

We will rely on energy (“power”) indicators officially given by rifle manufacturers, which, unlike speed indicators, are completely objective. The fact is that the weapons legislation of most countries is oriented specifically towards them, and such things are not joked about. Secondly, if most people have a good idea of ​​meters per second, then with all sorts of different joules not everything is so smooth. It’s like with car enthusiasts: the maximum speed in km/h (by the way, is also always overestimated) is understandable to any “blonde” but there are already problems with Newton meters of torque.

There is a fundamental formula E = mv2/2, where “E” is energy, “m” is mass, and “v” is speed. That is, all these quantities are interrelated and depend on each other. Let's carry out calculations of real performance of air rifles with different energy levels. Of the spring-piston 4.5 mm, we will focus on the license-free version up to 7.5 joules, “magnums” - 20 and 25 joules, as well as “supermagnums” - 30 J. We will consider weapons with pre-pumping (PCP) in three main calibers - 4.5 (.177), 5.5 (.22) and 6.35 (.25) mm; 37, 53 and 60 joules, respectively

So, what bullets do pneumatic manufacturers have in mind when they cite fantastic speed figures for their advertised rifles...

Airguns

Not long ago, a survey was conducted among pneumatic gun owners on the topic: “What is the bullet speed of your pneumatic gun?” Interestingly, the percentage spread across speeds is very variable.

So, for example, most of those who took part in the survey (20%) named the figure as 220-305 m/s. Since this is, in principle, a normal statistical average for pneumatics, the figure does not cause mistrust.

However, almost 9% of respondents claim that their weapon has a bullet speed of 380 m/s or more. This figure casts doubt on its reliability. The result is some kind of overly powerful military weapon. This value of bullet speed for pneumatics is rare; not every model can boast of this.

19% of participants admitted that their weapon hits at a bullet speed of 100-130 m/s and 130-180 m/s. For 11%, this figure tends to 350 m/s, which is quite serious. And finally, 6% of participants estimate the bullet exit speed in their pneumatic guns to be 75-100 m/s.

The most common and easiest way to measure speed on air guns is with chronometers. Most of these devices are designed specifically for pneumatics. Although the error in measurements will not go away, the result will still remain quite reliable.

No matter how you measure the speed of a bullet leaving your weapon, the error will still not go away, since the external environment will always be different in its indicators.

Air rifles

Quite recently, a social campaign was held among fans of air guns. survey - what is the maximum bullet speed of their pneumatics. By a strange coincidence, the range of answers varied greatly. A larger number of people surveyed said quite reasonable figures, namely 210-300 m/s. And these figures inspire confidence, since this is a standard indicator for this type of weapon.

Another part of the respondents, who claim that their pneumatic weapons have a bullet speed of 380 m/s, and even more, makes them doubt the reliability of their words. It turns out to be quite a powerful weapon. It can even be called combat. After all, not many types of pneumatic weapons have such indicators.

The rest answered that their pneumatic guns shoot at 110-120 m/s and 140-190 m/s. For some, the maximum bullet speed in the world tends to be 360 ​​m/s, and this is a fairly high figure. And for the rest, this figure is 75-110 m/s.

Typically, a chronometer is used to measure speed on air guns. After all, most chronometers were created precisely to measure a similar indicator in air weapons. Although chronometers have errors, they show fairly reliable values.

There are different methods for measuring projectile speed, and each of them has its own disadvantages. But errors cannot be eliminated, since the conditions under which measurements are carried out are always different. Therefore, the same weapon can show different results.

arbalet-airgun

This review is devoted to the most common 4.5 mm (.177) caliber air guns, mainly ammunition for spring-piston rifles.

Types and types of 177 caliber pneumatic bullets

First of all, they are characterized by the classic form of a “shuttlecock” or “reel” (pictured on the left) under the wonderful general name “Diabolo”. So-called ammunition The "ogival" form known to everyone from firearms is extremely rare (pictured on the right is the H&N Rabbit Magnum II).

This is due to the relatively low power of most 4.5 mm rifles. The small contact area between the bullet and the bore in the area of ​​the head section and the “skirt” noticeably reduces friction losses, but quite successfully resists gas breakthrough. For heavy-duty pre-pumped rifles ( PCP), starting from 30 caliber (7.62 mm), on the contrary, bullets of the “ogival” shape are characteristic.

But let's get back to our shuttlecocks.

Here are their main types:

Within each, there are various types and subtypes, differing in caliber, weight, technical details, ballistic characteristics and workmanship. The type of bullet depends primarily on the application.

Thus, flat-head bullets (“ Wadcutter”), often designated “ Match ,” which implies selective selection (and there are also super-elite “
Finale Match”)
, are mainly used for high-precision sports shooting from match rifles and pistols at a distance of 10 meters. They leave clear, round holes on paper targets for accurate scoring.

The photo shows their typical representative from the famous German company), whose products we will refer to repeatedly. These bullets are specifically used in Olympic shooting disciplines.

For obvious reasons, at hunting and recreational distances of 30 meters or more, “flathead” pellets are no longer effective. True, with low penetrating ability they have an increased stopping effect.

In the field of hunting, “plinking” and near-sport high-precision shooting, ammunition under the general name “ Domed ” (“dome”), which has a hemispherical (rounded) head, mainly reigns. They are the most versatile for any rifle and range.

The photo shows light, high-speed and very accurate bullets from the leading Czech company JSB, with which I once started and still have no intention of parting with them. In terms of quality, they are in no way inferior to German canned products; in this case, this refers specifically to quality and accuracy. For those interested in the topic, I suggest you watch the video given in the article “Video and photo reports from pneumatic weapon manufacturing factories.”

Let's move on from universal ammunition to specialized ammunition.

Bullets with a conical head (“ Point ”, that is, “point”), due to their increased penetrating ability, are advertised as allegedly hunting.

Frankly speaking, high penetrating power is needed mainly for punching holes in rolled metal for a bet, which is something that owners of budget “supermagnums” often do. For hunting, the requirements are completely different (see “What is more powerful - a bow, crossbow or pneumatic?”). In addition, the “JSB Exact Diabolo” bullets already mentioned just above, although not carbide, sew right through everything you need and don’t need with no less enthusiasm. Therefore, I use them exclusively for shooting at paper targets and, at most, with magnums. For serious tasks, use the heavy “H&N Baracuda Match” 10.65 gr”/0.69 grams (pictured), for “plinking” - “Crosman Premier domed” 10.5 grain/0.68 grams.

But let's return to bullets with a conical warhead. The fact is that these same “penetrated points” fly doesn’t matter. I read somewhere - and I agree with this opinion - that the tip itself is not always located strictly along the axis of the bullets, as a result of which they yaw in flight. Apparently, even the world's leading manufacturers are not always able to maintain the exact geometry of the projectile.

The situation is a little similar with actual hunting ammunition, known collectively as “ Hollow Point ” (“hollow point”, or “empty-headed”). It seems - in terms of low accuracy with long-range shots. But due to their design, at optimal firing distances they will transfer the maximum amount of energy to the game and cause lethal damage to internal organs, providing a high stopping effect.

Cavities can be different:

The bullet pictured on the right, when it hits the target, begins to open like a flower, literally tearing the flesh.

Again, for obvious reasons, the ballistic characteristics of such bullets are worse than those of conventional hemispherical ones. Same as the sample below.

Behind the formidable name “Terminator” is an attempt to create a kind of analogue of bullets with a core. That is, the combination of penetration (penetrating ability) and stopping action. If you are not chasing a long shot, such ammunition is quite effective (see “Terminator Pneumatic Bullet”).

Indeed, all “Hollow Points” at short and medium distances allow you to confidently work on game intended for pneumatics. If you look closely at the previous photo, you will notice that the manufacturer has combined almost incompatible things on the can’s label: the silhouette of a crow, as well as the indications “16 J” and “0.57 g”. That is, with the “Terminator” you can take a fairly serious bird from a 16-joule rifle with a light bullet.

Fortunately, owners of pneumatic guns, like smoothbore shotguns, have the right to experiment with ammunition on their own. Unlike owners of rifled weapons, who literally until recently could be seriously punished for reloading/reloading cartridges. For example, like this:

These are expansive hunting bullets made from standard (left) hunting bullets in five seconds. How they fly is another matter, but the fact itself...

Attention! If the article breaks off at this point, temporarily disable your ad blocker. Some of them manage to cut off the actual advertising screensavers along with the rest of the text. Moreover, they block the viewing of videos with stories about weapons, scenes of shooting or hunting.

Choosing a pneumatic bullet manufacturer

You probably noticed that among the photographs presented in the review there was not a single one with products that are familiar to most airgunners, such as “Gamo”, “Bumblebee”, “Lyuman”, “Oztey”, etc. But they are the ones who fill the store shelves. And they cost very attractively.

You can talk about them for quite a long time, but it’s better to see them once...

On the left is “Gamo”, on the right is “Bumblebee”.

Well, “insect” - okay. But with all due respect to the Spanish rifles and pistols, it clearly orders some brands of bullets under its own brand from distant third-party companies. Which is very strange, because El Gamo is the most famous and largest manufacturer of pneumatics and ammunition in Europe (!). It's not even a matter of flash, which indicates poor quality stamping and processing. The bullets may well turn out to be of the wrong caliber; in other words, they won’t fit into the barrel or will fall through. Or be oval in cross section, which is very clearly visible in the “skirts”. However, all these manufacturers have very decent models and batches of products.

Even the American one, whose “Premier” 10.5 gr I have been using for a long time and in large quantities, has noticeable instability in quality. Moreover, in a branded jar there may be crooked and dirty mutants, but in an ordinary pack there may be quite decent samples. It seems that this most popular mass brand has very widespread counterfeits, or more precisely, crude fakes. It is quite possible that the same applies to Gamo products. In short, be careful when purchasing.

That is, it is quite possible to simply shoot all of the above bullets. I am happy to provide both “Lyuman” and “Bumblebee” to guests for shooting from the “Hatsan”. Beer cans and other traditional “plinking” targets (see “Entertaining shooting from pneumatics and crossbows” ) sooner or later, to everyone’s joy, fall or shatter into pieces. Well, what else do you need on vacation?

In other cases, the savings are not justified. It is especially not recommended to use bullets from non-elite manufacturers for high-precision shooting “on paper” and hunting. Even more or less carefully made shells can differ greatly from each other in mass.

More on the topic: New air bullets

Weight, size and velocity characteristics of pneumatic bullets

Air rifles differ in “power” from firearms hundreds of times. Owners of the latter know how ballistic characteristics change when using bullets with a difference in weight of literally a gram or two. For pneumatics, accordingly, we are talking about hundredths of a gram, not to mention tenths.

In the article “Sighting distances for an air rifle for hunting” we calculated the ballistics for the same bullet fired from the same rifle, with a change in the “far zero”. The difference in elevations at the peak of the trajectory was 2 centimeters; beyond “zero” the discrepancy only grew. Something similar will happen if the bullets differ in mass, especially at long distances. And what even a couple of centimeters means during a hunt will become clear from the section on aiming for a wood pigeon in the article “Hunting with air rifles for pigeons.” Or in such a complex form as varminting. Let me emphasize once again: pneumatics are not firearms; the requirements for shot accuracy are much stricter here.

It is no coincidence that fans of high-precision shooting carefully wash even elite bullets, then scrupulously weigh them, trying to select, especially for competitions, samples that match the weight as much as possible.

This allows you to achieve stable performance and the same speed. Even mathematics testifies to the degree of its importance: for example, “quadraticity” in the formula E = mV2/2. Real, and not advertising, speed characteristics for the main classes of spring-piston rifles and the main types of bullets look approximately as follows, adjusted for design features, etc.:

• for “magnum” (approx. 20 joules): “half a gram” (0.55 g) - 280 m/s, “heavy” (0.68 g) - 240 m/s. "Hatsans" - up to 300 m/s.
• for “supermagnum”: (29-33 joules): “half a gram”, which is extremely undesirable - 330-340 m/s, “heavy” (0.68 g) - 290-310 m/s.

Advertising and marketing indicators (305 m/s for most magnums and 380 for supermagnums) , which have such a fascinating effect on beginners, are achieved by all manufacturers using especially light bullets, which will be discussed in the final part of the article. There will also be information about the specific speed characteristics of pre-inflated pneumatics.

Mathematical calculations with the calculation of real bullet speeds for various types of rifles and the corresponding ballistic tables are given in the article “Pneumatic bullet speed.”

Super-heavy bullets for the 177 caliber, weighing from 1 gram, are used exclusively for PCP rifles, most of which are one and a half to two times more powerful than any “super magnum” (in the photo “H&N Piledriver” 1.36 g).

Although PPP owners (myself included) are experimenting with similar ammunition, including homemade ones, like the “tandem” bullet glued together from two “half-grams” shown in the announcement photo of the future article.

And finally, about light bullets. They are categorically not recommended for any more or less powerful pneumatics. So-called "half-gram" (about 0.55 g) projectiles are desirable on weapons of 7.5-16 joules and are acceptable on any rifle up to 18-20 joules. For Khatsan “magnums” and any “supermagnums” a kind of standard is 10.5-10.65 grain (0.68-0.69 grams). Serious manufacturers, as a rule, indicate the optimal energy level directly on the can, for example, “16 J ” or “>25 J ”.

Anything that weighs less than half a gram is not a topic at all, with the exception of gas pistols and rifles up to 3 joules. These are not only the notorious penny DS “caps”, known to many generations from the Tirov “spirits” of the USSR (pictured), which are still produced today.

In terms of weight characteristics, their analogue is the projectiles known as PBA (“performance ballistic alloy”, or, loosely translated, “high ballistic characteristics”). More precisely, some of their types of 4.5 mm caliber are ultra-light (less than 0.3 grams) and do not contain lead bullets. Just in case you are a firefighter, I will repeat once again: they are intended for gas-cylinder 3-joule CO2 pistols and similar long-barreled pneumatics. But it is precisely for such projectiles that manufacturers and sellers, without particularly advertising it, give such attractive speed indicators in advertising articles and performance characteristics tables of serious rifles - 305 m/s for “magnum” and 360-380 m/s for “supermagnum” pneumatics. Gamo even produces these with platinum (!) coating.

True, we must pay tribute that at least this company, citing sky-high speed indicators, honestly indicates that “1300 feet per second (fps) with PBA Platinum” are achieved. That is, a speed of 1300 feet per second (396 m/s!) is only possible with the aforementioned ultra-light pellets. Most other manufacturers, especially in the budget segment, not to mention domestic sellers, are modestly silent about this.

I devoted a lot of “kind” words to ultra-light bullets - a nightmare invention for inattentive and gullible beginner airgunners - in the final part of the article “Powerful pneumatics: features of the national character.” If you are the owner of any rifle with more than 16 J of energy, be extremely careful when purchasing them, the weight should not be less than half a gram. Otherwise, you will get an almost complete analogue of a “blank” shot, which is destructive for serious rifles. And although they fly fast, they fly very crookedly. In addition, they are completely unsuitable for hunting purposes.

The same is true for pre-inflated pneumatics (PCP). In Russian stores it is mainly sold in calibers 4.5, 5.5, 6.35, 7.62 and 9 mm. True, the last two already refer to licensed hunting pneumatic weapons up to 25 J. In principle, by pushing an ultra-light bullet into the drum and working hard with the pump, you can achieve speeds exceeding 400 meters per second, almost at the level of a smoothbore firearm. However, in reality, PCP owners use ammunition that is suitable specifically for their weapon and optimize the pressure (the so-called “plateau”) or set the gearbox to, again, optimal values. Depending on the caliber, the weapon produces from 220 to approximately 320 m/s. Another thing is that even in 4.5 mm caliber, the power of such rifles allows you to use super-heavy bullets for spring-piston pneumatics and take much more serious prey.

Please also take into account this point: the silencers installed on most modern PCP rifles, like those on firearms, work correctly only at subsonic (up to 330 m/s) speeds.

Continuing the theme of “super-duper-speeds” and other pampering, we could also talk about shooting with matches, nails and ear cotton swabs (they are ideal in caliber and are used when cleaning rifles), but for one review of all of the above, I hope enough.

More “advanced” shooters know that each model and even a single rifle has its own optimal and safe ammunition for the device. They may well turn out to be light (!) bullets, only with a higher alloy hardness. In this case, the breaking force is large enough to cause the phenomenon of a “idle” shot. But to correctly determine the characteristics of specific bullets, you will have to run various models of the same weight category down the barrel and evaluate this force. In this case, control shootings through a chronograph are required to assess changes in speed (and therefore energy) and accuracy, seeing if these indicators “float away”, and settling on some optimal ratio. In general, this would not hurt for any rifle, but not everyone has the appropriate equipment or knowledge. Whether it’s worth experimenting for you personally - decide for yourself.

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