Automatic shotgun

An automatic shotgun is an automatic firearm that fires shotgun shells and uses some of the energy of each shot to automatically cycle the action and load a new round. It will fire repeatedly until the trigger is released or ammunition runs out. Automatic shotguns have a very limited range, but provide tremendous firepower at close range.

Automatic shotguns generally employ mechanisms very similar to other kinds of automatic weapons. There are several methods of operation, with the most common being gas, recoil, and blowback operated:

Each of these methods use springs to return the retracted parts to their forward positions and restart the cycle.

Many automatic shotguns are capable of selective fire, meaning they can fire in multiple modes (semi-automatic, three-round burst, and sometimes fully automatic).

They generally store ammunition in detachable box or drum magazines in order to decrease reloading time, whereas most pump-action and semi-automatic shotguns use under-barrel tubular magazines.

Shotguns are able to handle a wide variety of ammunition, however automatics are slightly limited because the shot must provide sufficient force to reliably cycle the action. This means that they are not compatible with low powered rounds, like most less-than-lethal ammunition. The most common ammunition used in combat shotguns is 00 buckshot, which fires about 9 metal balls and is very effective against unarmored targets.

A standard shotgun shot fires multiple small projectiles at once, increasing the chances of hitting the target. Shotguns have a short effective range of about 50–70 metres (160–230 ft), but provide a lot of firepower at close range. Automatic fire enhances these effects, due to the increase in the rate of fire.

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