The blank firing barrel can be machined from a solid block of metal such as stainless steel so that {HEAD ~ the barrel end} is {TAIL ~ a contiguous portion} of the original solid metal block 
is
The blank firing barrel can be machined from a solid block of metal such as stainless steel so that { HEAD ~ the barrel end } is { TAIL ~ a contiguous portion } of the original solid metal block
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH