A friend asked this question after unknowingly firing grenade cartridges in his M1 with BFA installed. As was part of the M1 later design the rear of the receiver failed as it should and luckily my buddy didn’t have his jaw taken off. Anyway, he has now found another receiver and asked what he should do about the original? Not knowing who else to ask maybe someone here has some insight into what is required to decommission an ATFB regulated part.