Re: Free brass
They are blanks. They, in their usual load configuration don't produce enough pressure to operate the MG's action. Usually a blank firing adapter is necessary. Problem: we don't know whether the case has the same tensile strength characteristics of regular ammo.If you want to know, you could cut the "bullet" off, expand the neck and trim to length, seat a bullet and see if the thickness is within specs for regular ammo, then reload one to your normally used load. Measure the case head across the base. Chamber the round and fire with a long string. If YOUR RIFLE survives, measure the after fired case head expansion. If less than .001" then it is probably ok. If the rifle blows up, then let us know so we have the definitive answer.