this may have been one of the green gas guns not the battery guns we all know. the green gas guns use a real firing pin and with that said and has a bolt that moves too the lowers are the same function as the real guns (a friend has a 1911 that works like that and all 1911 parts fit it,grips,triggers,safeties and so on) so if that is the model and alot are made of alloy metals, it may have been easily converted as the trigger and mechanics work like a m4/m16. dont know if you could get more than one round off b4 it came apart (sure the recoil buffer and tube were not intended for real recoil of a .223/5.56) but can see this being the intent of the seizure of the toys