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