Bob,
My dead center is a slip fit into the back of the spindle. It's made of aluminum and has stainless centers on each end. One center is turned for a pilot for removable bushings, either .22 cal or 6mm. I like the bushing because it keeps the barrel from falling off the center when you're moving the barrel around. How close to center it actually has to be, I don't know. I talked to Troy Newlon one time. He said he used the cardboard bushings that he uses to ship his dies to hold up short barrels on the back end of his lathe. Ron Hoehn also uses some kind of a bushing set up to hold up the muzzle end of his barrels.
When I bought my lathe, I bought a shell reamer that had been used to ream the spindle of another Kent owner's lathe. I ran the reamer through holding the back of a long bar using the carriage to drive the shell reamer through the spindle. When finished the inside hole of the spindle had .0005" runout. I probably have a little more runout than that on the dead center due to the slip fit having a thousandth or so clearance plus tolerance stack. It's probably not that important what you use or how much runout you have at the muzzle. It doesn't seem to make that much difference with Gordy's method and I'm not sure that it makes much difference if you use the method that I use indicating the barrel in at the projected throat and drilling and boring out most of the chamber.
Just as a test one time, I took a Shilen #4 contour barrel, ran it between centers and turned the cylinder end concentric between centers which it was probably pretty close anyway. Took the cylinder and chucked it up in the lathe chuck with the muzzle end hanging loose. Indicated the bore at the projected throat, drilled and bored out most of the chamber and chambered the barrel. The barrel in .30-06 installed on a trued Sako will easily shoot 1/2" accuracy. We don't know just how well it will shoot as we're still shooting the same load that we threw together and haven't wasted hardly any bullets downrange working up loads for it. It's plenty accurate for a deer rifle even for shots pretty far out.
Sorry I didn't see your question sooner, but I've been building rifles and don't spend a lot of time on the forum's anymore.
Mike
Paul,
The Kent lathe that I have is a copy of a Clausing Colchester adapted by Kent to use a VFD drive. The non VFD drive lathe they make is just about a direct copy of the Clausing Colchester. Rex Reneau uses a Clausing Colchester. I'll have to ask him what he uses to chamber short barrels.
Mike
