Fastening the barrel muzzle-up, heat the barrel and the rod from the muzzle down to the packing point,
with a torch until it is hot. Make sure that the rod is central in the bore; pour in melted nickel-Babbitt
around the rod until the barrel is full to the muzzle. After it has cooled, withdraw it partly from the barrel
and shave off the outer end, where it overflowed the muzzle.
Make a punch mark on the muzzle of the barrel at one of the grooves and mark the Babbitt slug on the
end opposite this mark on the barrel. If this guide block is removed from the guide barrel, you will get it
back in the same position in which it was cast. Remove the waste from the barrel and clean the barrel
out well. Reinsert the rod and guide block in the guide barrel, and then attach to the rear end of the rod a
cross-handle, mounted on the rod on ball bearings.
The rod, with the guide in place in the guide barrel near the end closest to the barrel to be rifled. This
should be long enough so the rifling cutter clears by an inch or more the opposite end of the barrel to be
rifled. With the clamps all locked and the rifling cutter in position in the head, the rifling cutter is now
drawn through the barrel to be rifled, making the first cut.
The cutter is then dropped down, or, if it is the shimmed-up type of hook cutter, it is removed from the
rifling head and the head is pushed back through the barrel. The cutter is replaced and the clamps on
the guide barrel are loosened. Then the index pin is withdrawn and the guide barrel revolved in the
clamps to the next pinhole, the pin is replaced. The clams are tightened and the cutter is again drawn
through the barrel to make a cut for the second groove.
This process is repeated with the same cutter setting until one cut has been made in each groove. The
cutter is then raised and a second cut is made in the first groove, and all this is repeated until the
grooves are all cut to the proper depth. The guide barrel must be kept well oiled on the inside and the
barrel being rifled must have with cutting oil, either lard-oil or black sulfur oil compound pumped through
it.
This cutting oil should be pumped into the barrel under pressure so that it will wash out the chips. It is
better to use a tube for a pull-rod, as the oil line from the pump can be attached to the end of the tube
opposite the rifling head. The oil can be pumped into the barrel by this method by having oil outlet holes
drilled in the rifling head. A pump can be purchased from a machine shop supplier for this purpose. As
the oil leaves the barrel it is screened to remove chips and is returned to the sump from which it is
pumped.