Patent ID: 7942090

Claim:
A blank firing attachment for a gas-operated weapon having a barrel, the barrel having a bore with a cross-sectional area, the blank firing attachment comprising: a housing having first and second ends; a stem supported at the first end of the housing and extending along a longitudinal axis of the housing, the stem for insertion into the bore of the barrel, the stem having a cross-sectional area less than the cross-sectional area of the bore; said stem being manufactured of tungsten carbide having a uniform microstructure, with a maximum grain size of less than 1 micron, a minimum tungsten carbide content of about 80%; a minimum cobalt content of about 10%; and a minimum hardness on the Rockwell A scale of 91; and means for attaching the housing to said barrel; wherein, upon firing a blank cartridge in the weapon, a difference between the cross-sectional area of the bore and the cross-sectional area of the stem is an area small enough to generate sufficient backpressure in the bore as to operate the weapon and large enough to bleed excess gas from the system as to prevent an overpressure condition in the bore.