FIGS 1 and 2 illustrate {HEAD ~ an automatic firearm} 20 of {TAIL ~ the gas operated type} 
of
FIGS 1 and 2 illustrate { HEAD ~ an automatic firearm } 20 of { TAIL ~ the gas operated type }
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL