Discovery Channel: Future Weapons. Force Multiplier especially with the frag-12 mini-grenades and high explosive. Accurate out to 175 meters. 120 grenade rounds per minute with 9 foot blast radius.
The gist of the story is that the AA-12s have so little recoil that it makes the perfect gun for small robots.
AA12 shotgun robots at zokuga blog
Wikipedia on the Auto Assault-12 (AA-12) shotgun (originally designed and known as the Atchisson Assault Shotgun).
The weapon can fire in semi-automatic or fully automatic mode at 300 rounds per minute (5 every second) and has a magazine of 32 rounds - either a standard box, or a drum magazine. MPS also teamed up with Action Manufacturing Company, and Special Cartridge Company to combine the gun with FRAG-12 High-Explosive ammunition into a weapon system.
The weapon was shortened to 966 mm but retained same barrel length as the original, and lightened to 4.76 kg. The CQB model has 13-inch barrel length, and is half a pound lighter than the regular model. Uncommon in other automatic shotguns, the AA-12 fires from an open bolt, a feature more commonly found in heavy and squad level machine guns. It uses 8-round box, 20-round drum, or 32-round drum magazines, as opposed to the original 5-round box magazine. It is designed to fire three different types of 3" 12 gauge shells: Buckshot, slug, or Frag-12 rounds. Due to the abundant use of stainless steel, and the loose manufacturing allowed in a shotgun, MPS has claimed that the weapon requires zero cleaning or lubrication.