Been a while...my son asked me to look around for an upper receiver for his pos vulcan chambered in .223. He just text me and said it was in three pieces?? I never got an answer as to why the failure, but can only imagine. I told him long ago to get rid of the pos...with it's screw on, sloppy fitting barrel to it's cheap plastic receiver. Any way I am asking if there may be compatible upper receivers of an alloy construction and or should he start from the ground up with a more reliable manufacturer?