BOLT,AUTOMATIC WEAPON - United States (US)
An item consisting of a bolt carrier, a breech bolt, a top plate, and a locating pin. It replaces a breech bolt in a rifle or machine gun to alter the operation of the weapon from gas to blow-back so that low-powered practice ammunition may be used. It is not intended for non-practice usage. Excludes BOLT, BREECH and BREECHBLOCK.