It comprises {TAIL ~ a receiver assembly} 22, having {HEAD ~ an upper chamber} 24 for receiving a bolt assembly 26 
It comprises { TAIL ~ a receiver assembly } 22 , having { HEAD ~ an upper chamber } 24 for receiving a bolt assembly 26
OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH