Atchisson AA-12

Atchisson AA-12
AA-12 automatic combat shotgun
Type	Automatic combat shotgun
Place of origin	United States
Production history
Designer	Maxwell Atchisson (1930–2003); further developed by Military Police Systems, Inc.
Designed	Original design: 1972 MPS design: 2005
Manufacturer	Maxwell Atchisson[1]
Specifications
Mass	5.2 kg (11 lb) less magazine. 7.3 kg (16 lb) with loaded 32-round drum (original version)
Length	991 mm (39.0 in) (Atchisson Assault Shotgun, 1972) 966 mm (38.0 in) (AA-12, 2006)[2]
Barrel length	457 mm (18.0 in)
Cartridge	12 gauge
Action	API blowback[2]
Rate of fire	300 rounds/min[3]
Muzzle velocity	350 m/s (1,100 ft/s)
Effective firing range	100 m (110 yd) (12 gauge slug)
Maximum firing range	200 m (220 yd) (FRAG-12 ammunition)[4][3]
Feed system	8 rounds in box magazine, 20 or 32 rounds[5] in drum magazine
Sights	Iron sight, 2× zoom optical scope

The AA-12 (auto assault-12), originally designed and known as the Atchisson Assault Shotgun, is an automatic combat shotgun developed in 1972 by Maxwell Atchisson (however, the original development by Atchisson seems to have produced only a few guns at prototype-level, with the development that ultimately lead to the gun entering the market being done later by Military Police Systems, Inc.^[6]). The most prominent feature is reduced recoil. The current 2005 version has been developed over 18 years since the patent was sold to Military Police Systems, Inc. The original design was the basis of several later weapons, including the USAS-12 combat shotgun. The shotgun fires in fully automatic mode only. However, the relatively low cyclic rate of fire of around 300 rounds per minute enables the shooter to fire individual rounds through the use of short trigger pulls. It is fed from either an 8-round box magazine, 20-round drum magazine, or a 32-round drum magazine. The charging handle is located at the top of the gun and does not reciprocate during firing.