Destructive device

In the United States, a destructive device is a type of firearm or explosive device regulated by the National Firearms Act of 1934, revised by the Omnibus Crime Control and Safe Streets Act of 1968 and Gun Control Act of 1968.

Examples of destructive devices include grenades, and firearms with a bore over one half of an inch (.50 inches or 12.7mm), including some rifles and shotguns, both semi automatic and manually operated. While current federal laws allow destructive devices, some states have banned them from transfer to civilians. In states where banned, only law enforcement officers and military personnel are allowed to possess them.

All National Firearms Act firearms including destructive devices, must be registered with the Bureau of Alcohol, Tobacco, Firearms and Explosives.

The definition of a "destructive device" is found in 26 U.S.C. § 5845(f). The definition reads as follows:

The term "Secretary" originally referred to the Secretary of the Treasury, as the National Firearms Act is part of the Internal Revenue Code of 1986—since the BATF's transfer to the Department of Justice in 2002, the term "Secretary" now refers to the Attorney General.

Muzzle-loading guns are not considered firearms in the US and do not fall under the regulations of the NFA. However, their projectiles may still be subject to NFA regulation. For instance, a person may manufacture, possess and fire a black powder, muzzle-loading cannon of any bore diameter, but may not fire explosive shells from that cannon, as the explosive shell is itself defined as a destructive device.

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