Sawed-off shotgun

A sawed-off shotgun (US, CAN) also called a sawn-off shotgun (UK, IRL, AU, NZ) and a short-barreled shotgun (SBS) (U.S. legislative terminology), is a type of shotgun with a shorter gun barrel—typically under 18 inches—and often a shortened or absent . Despite the colloquial term, barrels do not, strictly speaking, have to be shortened with a saw. Barrels can be manufactured at shorter lengths as an alternative to traditional, longer barrels. This makes them easier to transport due to their smaller profile and lighter weight. Additionally, they make for popular guns for backpackers or campers, especially with regard to animal defense. The design also makes the weapon easy to maneuver in cramped spaces, a feature sought by military close quarters combat units, law enforcement SWAT team users, and home defense purposes. With modern pump action/magazine tube shotguns, the shorter barrel limits the magazine capacity of the weapon due to the magazine tube protruding beyond the barrel. Therefore the magazine tubes are matched in length to the barrel, which causes a reduction in the number of shells that can be held in the magazine tube.

In the 1930s, the United States, Britain and Canada mandated that a proper permit is required to own these firearms. They are subject to legal restrictions depending upon jurisdiction. They also are in use by military forces and police agencies worldwide.

Compared to a standard shotgun, the sawn-off shotgun has a shorter effective range, due to a lower muzzle velocity and wider spread of shot. Despite these drawbacks, its reduced size makes it easier to maneuver and conceal. Powerful and compact, the weapon is especially suitable for use in small spaces, such as close quarters combat in a military context. Military vehicle crews use short-barreled combat shotguns as ancillary weapons. In urban combat zones, military entry teams often use entry shotguns when breaching and entering doorways.

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