The AA-12 is rightfully considered one of the best automatic shotguns. It was appreciated by the American Marines, in addition, they were installed on AutoCopter unmanned helicopters and on the turrets of the HAMMER defense system.
This weapon also appeared in cinema. In particular, the main character of the film “Predator”, as well as one of the characters in the film “The Expendables,” was armed with just such a shotgun.
Description
The AA-12 self-loading shotgun provides two types of magazines: box magazine for 5 and 8 rounds, drum or disc magazine for 20 or 32 shots.
In 2000, the rights to produce the AA-12 were acquired by the American company Military Police System, which planned to equip the American army and police with these shotguns. Actually, just after this, in 2004, these guns entered service with the Marine Corps.
And they were created in 1981 by Maxwell Atchisson on the basis of another of his inventions – the 1972 Atchisson Assault Shotgun. The very idea of creating semi-automatic shotguns arose among American designers after the Vietnam War, where shotguns worked very well at short distances in dense jungles and indoors. These were the weapons of the Cold War era. The weapons of modern times should have been different. I wanted to achieve a higher rate of fire. And the most effective way to achieve this is automatic recharging.
Then the idea of developing an automatic shotgun appeared. And several talented designers took on this work at once. Atchisson was among them.
AA-12
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In the early 1980s, Atchisson redesigned his Atchisson Assault Shotgun to use a more traditional gas-operated gun combined with a rigid barrel lock. The reason for this modernization was the prospect of using more powerful special cartridges in smooth-bore military weapons, including those with arrow-shaped striking elements.
In addition to the use of new automation, Atchisson changed the design of the trigger mechanism and receiver. The new gun, named AA-12 , had a gas piston located above the barrel that operated the bolt. Locking was carried out by a wedge movable in a vertical plane located in the front part of the bolt. To lock, the wedge rose up and entered a groove in the barrel shank, thereby unloading the receiver.
Sketch AA-12. taken by Atchisson in 1985
The receiver was made integral with the forearm and butt and consisted of two halves, left and right, connected by pins. The butt was hollow, since after the shot the bolt rolled back into it. The trigger mechanism made it possible to fire single shots and bursts; shooting was still carried out from an open bolt. The cartridges were fed from detachable magazines similar to those from early Atchisson rifles.
One of the interesting features of the gun is the “recoil impulse accumulation” system, which consists of the interaction of a pair of return springs that stretch the recoil impulse over time, similar to that of the Ultimax 100 machine gun, which made it possible to significantly reduce recoil during automatic fire.
The AA-12 combat rifle was 26 cm shorter and almost half a kilo lighter than the earlier model.
For two decades, Atchisson improved his AA-12 gun, but things never reached mass production. In 1987, due to the threat of bankruptcy, he sold the rights to the shotgun to Jerry Baber of the American company Military Police System . The latter is a brilliant engineer with extensive experience in weapons production. Together with his partner Boje Corneal , a talented German engineer, Jerry began making copies of the shotgun for pre-sale demonstration to potential customers (US Army and Police). However, the engineers were dissatisfied with the resulting characteristics and began to modify it, and after 188 improvements, they got what, according to some experts, is the best assault shotgun in the world.
The shotgun does not require special care and lubrication, since, according to the developers, self-lubrication and self-cleaning occurs when firing. Cleaning should be done after every 8000-9000 shots.
The body of the shotgun is made of durable plastic, which can be painted in any camouflage color.
The AA-12 is produced in two versions - regular and AA-12 CQB (Close Quarters Battle) with a shortened barrel for close combat.
Regular and CQB variant AA-12
In 2004, 10 examples of the AA-12 were created and demonstrated to the US Marine Corps, which showed great interest. The "HAMMER" defense system, created by More Industries, uses dual AA-12s on H2X-40 turrets. And Neural Robotics installed the AA-12 on its AutoCopter unmanned aerial vehicle.
Characteristics of AA-12:
- type - automatic, gas-operated automatic with barrel locking
- caliber - 12
- length - 965 mm
- barrel length - 457 mm
- weight - 4.76 kg without magazine
- food - 8 rounds in a box magazine or 20 in a drum magazine
- rate of fire - 360 rounds per minute
- effective firing range - 100 m (for bullet cartridges of 12th
- caliber), 200 m (for FRAG-12 cartridges)
The AA-12 Automatic Assault Shotgun is particularly effective with FRAG-12 , ideal for bridging and engaging lightly armored vehicles, something the US Marine Corps has become interested in.
FRAG-12 shells were developed in 1994 by British companies Experimental Cartridge Company, Ltd. and Action Manufacturing Inc. Successfully passed field tests as ammunition for special forces.
FRAG-12 projectiles are available in the following versions:
- high explosive - HE (High Explosive)
- high-explosive fragmentation - HE-FA (High Explosive Fragmenting Antipersonnel)
- armor-piercing high-explosive - HE-AP (High Explosive Armor-Piercing)
To improve shooting accuracy and shooter safety, the FRAG-12 is supported by barrels with a choke installed. They were designed specifically for automatic and semi-automatic shotguns with a gas-operated system combined with a rigid barrel lock, such as the AA-12.
FRAG-12 is a conventional 12-gauge rifle cartridge, inside which is placed a projectile with a diameter of 19 mm with a stabilizing tail, which opens when it leaves the barrel and moves away from it at a distance of three meters.
The FRAG-12 HE high explosive projectile penetrates 6.3 mm (¼ inch) cold rolled steel plate. At the same time, the maximum effective firing range of these charges reaches 200 meters, which is beyond the capabilities of standard shotgun ammunition.
The armor-piercing high-explosive FRAG-12 HE-AP penetrates 12.7 mm (½ inch) steel armor, which makes it possible to effectively disable enemy vehicles, for example, when defending checkpoints, as well as destroy potential explosive devices from a distance.
Design
He took as a basis a system that had not previously been used for smooth-bore shotguns, but had proven itself well for submachine guns: blowback automatic. This made it possible to significantly reduce the recoil force and rate of fire. Actually, the rollback of the free bolt was the main principle of operation of the system of this combat shotgun. After the shot, the powder gases pushed the cartridges back, and with it the rather heavy cylindrical bolt, which already compressed the return spring.
To ensure low recoil when firing in bursts, the receiver reached the butt plate, thereby increasing the length of the bolt's recoil. This made it possible to almost completely extinguish the impulse of the shot, which explained the rather low recoil.
Low recoil is very important in automatic weapons chambered for 12 gauge to ensure proper accuracy. Otherwise, burst fire will simply be ineffective.
Reducing recoil for the shooter, the designer distributed its effect throughout the shotgun mechanism. This had a particularly strong effect on the reliability of the magazine mounting. The metal bracket, together with the pistol grip, acts as a stop that secures the magazine.
The second feature of the AAS shotgun is that it fires with the bolt open. After the shooter presses the trigger, the bolt is released under the influence of the return spring and only then does the cartridge primer puncture.
The AA-12 differs from its predecessor in many ways. Even his appearance has seriously changed. Now the body of the shotgun has become solid: the hollow plastic butt, which covers the receiver and goes into the fore-end, consists of left and right halves, attached to each other with pins. But it’s not enough to change the shape of the butt; the trigger has also been redesigned. Starting with the use of a more advanced system with a gas outlet tube and two return springs. This made the shotgun more reliable and further reduced recoil. Now the barrel is rigidly locked using a wedge that fits into the breech groove.
The barrel length was also changed downward and the weight was reduced.
AA-12 in camouflage
About tactical and technical characteristics
AA 12 has the following parameters:
- Weapon type: gas operated automatic shotgun.
- Type of ammunition: 12-gauge hunting cartridges.
- The entire length of the shotgun is 965 mm.
- Barrel length 457 mm.
- The weapon weighs 4.75 kg without ammunition.
- The weight of a shotgun equipped with eight cartridges is 5.08 kg.
- The weight of a weapon using a drum magazine is 5.88 kg.
- A maximum of 360 shots can be fired from a shotgun within one minute.
Advantages and disadvantages
The undoubted advantage of the AA-12 automatic shotgun is its high accuracy and high efficiency at short distances. However, as the range increases, the effectiveness quickly decreases. Actually, the shotgun was created for short-range combat. So he copes with the task assigned to him.
In addition, the designer managed to minimize recoil when firing in bursts. Considering that we are talking about fairly powerful 12-gauge ammunition, reducing recoil is a top priority. The ability to choose a magazine for the required number of shots is also a plus of this model. The 5- and 8-round box magazine is more compact and lightweight, but the 20-round magazine increases the number of shots. The security of the system is at a high level, which can also be considered an advantage.
The disadvantage is the heavy weight. Of course, compared to the earlier version, the gun weighs less. And yet it is quite heavy.
Ammunition
The original version of the gun, the Atchisson Assault Shotgun, was intended to fire standard 12-gauge ammunition with a 70 mm case and a Magnum cartridge with a 76 mm case. Both cartridges could be equipped with both buckshot and various bullets.
The AA-12 is capable of firing these cartridges, but is also adapted to fire the more powerful FRAG-12 ammunition. There were rumors that the ammunition itself was developed specifically for this shotgun, but it is impossible to verify them.
FRAG-12 is seriously different from its predecessors. The bullet has a special design: a metal shell on the outside, and various fillings on the inside. Additionally, when the bullet leaves the barrel, its tail surface opens. It is this that allows you to stabilize the flight of the projectile, and this, in turn, increases shooting accuracy. The FRAG-12 cartridge from the AA-12 shotgun can be accurately fired at a distance of up to 200 meters.
The bullet filling in the FRAG-12 cartridge can be of three types:
- HE – high explosive;
- HE-FA – high-explosive fragmentation;
- HE-AP - armor-piercing bullets that combine cumulative and high-explosive effects.
If you shoot bursts of buckshot from an AA-12 shotgun, you get a dense cloud of damaging elements. For short distances or indoors this is ideal. However, as the distance increases to 70 meters, such shooting loses its effectiveness.
If the shooting distance is higher, then it is better to use single shots with ammunition loaded with a lead or steel bullet, depending on the target. Targeted burst fire over long distances is only possible with the FRAG-12 cartridge.
