I do it by making a short steel bushing with a taper bore to match the
barrel contour about 3" from the muzzle. The bushing OD can be whatever is
convenient, but make the wall thickness at least 1/4" . The bushing is
seated firmly on the barrel on a piece of heavy paper cut to fit the bushing
bore. The paper protects the finish and gives a good friction fit to the
bushing. Then chuck the barrel threads in your 3-jaw (brass or aluminum
shim stock over the threads). Put a live center into the tail stock and
engage bore at the muzzle. Install your steady rest on the lathe bed but
moved to a spot away from the muzzle. Run the lathe at about 250RPM and
true up the OD of the bushing, taking very light cuts. Don't be alarmed if
the barrel OD seems to wobble as many barrels are not perfectly straight and
many have an exterior that is not concentric with the bore.

Now move the steady rest to bear on the bushing and adjust to a close
running fit with plenty of lubrication. Move the tailstock back and you now
should have full access to the muzzle end for threading, recrowning, etc.
The bore should appear motionless when the lathe is running. If it doesn't,
you did something wrong.

If you have a non-tapered barrel, a split(one side) bushing with a clamp
screw will work the same. Just make the bushing long enough so the steady
rest jaws don't have to ride over the screw hole.

Randy



wrote in message
m...
I want to make a muzzle break for my gun. I am just learning to run my
lathe. The question I have is how do I hold on to the tapered barrel so
that I can turn the threads on the end of my gun barrel? Those with
experience pleas help me.

Thanks, KT