{HEAD ~ The breech block} has {TAIL ~ at least one bore} which receives a locking element supported for radial movement in the bore 
has
{ HEAD ~ The breech block } has { TAIL ~ at least one bore } which receives a locking element supported for radial movement in the bore
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH