barrel length

A sawed-off shotgun also called a sawn-off shotgun and a short-barreled shotgun, is a type of shotgun with a shorter gun barrel—typically under 18 inches—and often a shortened or absent stock. 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. 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. As a result of the shorter barrel length, any sawed-off shotgun with a magazine tube will have its capacity reduced.
In the 1930s, the United States, Britain and Canada mandated that a permit be required to own these firearms. They are subject to legal restrictions depending upon jurisdiction. They are used by military forces and police agencies worldwide.

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