Definitions.

For the purposes of this subchapter, the term “weapon” means a firearm and includes: Any weapon, including a starter gun, which will or is designed to or may be readily converted to expel a projectile by the action of an explosive: The frame or receiver of any weapon described in this subsection; Any firearm muffler or firearm silencer; or Any destructive device; the term “destructive device” means: Any explosive, incendiary, or poison gas; Bomb; Grenade; Rocket having a propellant charge of more than 4 ounces; Missile having an explosive or incendiary charge of more than a 1/4 ounce; Mine; or Any similar device. Any type of weapon which will, or which may be readily converted to, expel a projectile by the action of an explosive or other propellant, and which has any barrel with a bore of more than 1/2 an inch in diameter; and Any combination of parts either designed or intended for use in converting any device into any destructive device described in subparagraphs (e) and (f) of this paragraph and from which a destructive device may be readily assembled. The term “weapon” shall not include: An antique firearm; Any device which is neither designed nor redesigned for use as a weapon; or 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.