During the first weekend of the fall 2014 shoot, Bill Hoover and his friends did a demonstration of rifling a muzzle loading rifle barrel. While Bill’s rifling machine can cut multiple grooves, today the machine was set up to cut five grooves and a progressive or gain twist. In this set up the twist varied from 1/68” to 1/34” in a 42” barrel.
As we talked, Bill and Philip Iles worked on the machine. Philip would pull the cutter through a groove 10 times. Bill would then re-index the machine and clean the cutter with thread-cutting oil. After the cutter had been through each groove, Bill added a .001” steel shim under the cutter. The process would continue until he reached .006-.007” deep.
Bill’s cutters are made from taps. Since the bore of this barrel is .465″, a cutter made from a 1/2″ tap was used. the result is a groove with a radius that matches the radius of the bore.
Beside Bill’s rifling machine, John Kleihege was reaming a barrel on his machine. He had just finished reaming the rifling from an old rusty barrel. When his barrel was completely smooth, it would be ready for Bill to cut the rifling. The photos here were taken while I talked with Bill as he operated he rifling machine.
Larry Pletcher, editor, www.blackpowdermag.com