Short barreled rifle

Short-barreled rifle (SBR) is a legal designation in the United States, referring to a shoulder-fired, rifled firearm, made from a rifle, with a barrel length of less than 16 in (41 cm) or overall length of less than 26 in (66 cm). In the United States, an SBR is an item regulated by the Bureau of Alcohol, Tobacco, Firearms and Explosives (BATFE) as a Title II weapon. In the absence of local laws prohibiting ownership, American civilians may own an SBR provided it is registered with the BATFE, and a $200 tax is paid prior to taking possession of or creating the firearm.

The regulation of short-barreled rifles was the result of the National Firearms Act of 1934 which also imposed restrictions on short barreled shotguns, silencers and machine guns.

Overall length is measured between the extreme ends of the gun, along a centerline which passes through the middle of the barrel. For rifles fitted with folding or telescoping (such as U.S. Carbine M1A1), US Federal guidelines state that measurement is performed with the stock unfolded as intended for use as a rifle. Exception is made for rifles with easily detachable shoulder stocks, which shall be measured with the shoulder stock detached. Some states — such as California and Michigan — measure overall length with the stock folded. Barrel length is measured from the end of the muzzle to the front of the breechface, typically by inserting a measuring rod into the barrel. Barrel length may partially comprise a permanently attached muzzle accessory (such as a recoil compensator or flash suppressor).

SBRs may be created by trimming down a larger rifle, by building a rifle with an original barrel shorter than 16 in (41 cm), or by adding a shoulder stock to a handgun which is fitted with a barrel shorter than 16 in (41 cm), thereby legally redefining it as a rifle rather than a handgun. Each of these processes must legally be accompanied by BATFE registration. Certain old handguns originally available with shoulder stocks, such as original broomhandle Mausers or Lugers manufactured before 1946, more likely to be valued as curios or relics than as weapons, have been removed from federal SBR restriction but may be restricted under local gun laws. Certain "trapper model" rifles manufactured before 1934 with barrels under 16 in (41 cm) have similarly been removed from federal SBR restriction (the BATFE publishes a Curios and Relics List of models and serial number ranges). While SBRs on the Curio & Relic List are not "firearms" regulated under the 1934 National Firearms Act, they are still "firearms" regulated by the Gun Control Act of 1968.

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