The Atchisson Assault Shotgun, also known as the Auto Assault-12 or AA-12, is a combat shotgun developed in 1972 by Maxwell Atchisson. The shotgun fires 12 GA cartridges with a muzzle velocity of 350 m/s (1,100 ft/s), has a length of 991 mm, and weighs 5.2 kg. 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 weapon is fully automatic, but only fires at a rate of 300 rounds per minute; making it possible to fire one round at a time with brief trigger pulls. It is fed from either an 8-shell box magazine, or a 20- or 32-shell drum magazine. It was used by Kenny in "Buried", "To'hajiilee" and "Ozymandias".