(A) any weapon (including a starter gun) which will or is designed to or may readily be
converted to expel a projectile by the action of an explosive;

(B) the frame or receiver of any such weapon;

(C) any firearm muffler or firearm silencer; or

(D) any destructive device. Such term does not include an antique firearm.

 

As defined in 26 USC subsection 5845(f) (2) the term destructive device includes any type of weapon by whatever
name known which will, or which may readily be converted to, expel a projectile by the action of an explosive or
other propellant, the barrel or barrels of which have a bore of more than one-half inch in diameter, except a shotgun
or shotgun shell which the Secretary or his delegate finds is generally recognized as particularly suitable for sporting purposes; and (3) any combination of parts either designed or intended for use in converting any device into a
destructive device as defined in subparagraphs (1) and (2) and from which a destructive device may be readily
assembled. The term 'destructive device shall not include any device which is neither designed nor redesigned for
use as a weapon; any device, although originally designed for use as a weapon, which is redesigned for use as a
signaling, pyrotechnic, line throwing, safety, or similar device; surplus ordnance sold, loaned, or given by the
Secretary of the Army pursuant to the provisions of section 4684(2), 4685, or 4686 of title 10 of the USC; or any
other device which the Secretary of the Treasury or his delegate finds is not likely to be used as a weapon, or is an
antique or is a rifle which the owner intends to use solely for sporting purposes.

It is unlawful for anyone to make or possess a destructive device which is not registered in accordance with the
provisions of the National Firearms Act.

We have previously examined that certain muzzle loading devices known as "potato guns." These potato guns are constructed from PVC plastic tubing. They use hair spray or a similar aerosol substance for a propellant and have
some type of spark igniter. We have determined that these devices, as described, are not firearms provided that
they are used solely for launching potatoes for recreational purposes. However, any such devices which are used
as weapons or used to launch other forms of projectiles may be firearms and destructive devices as defined.

Bureau of Alcohol, Tobacco, and Firearms
Firearms Technology Branch, Room 6450
650 Massachusetts Avenue NW
Washington, DC 20226

Sincerely yours,