There sure are a lot of opinions on this. When I posted earlier, the question was about a 6jaw, and has flowed into a chambering method thread.

Again, there are many ways to skin this thing. Personally, I set up thru the headstock and never move it until all rear-end work is done. I do check indication after each step, just make sure all's well.

I use a 4jaw and spider. A set-true chuck is basically a 4jaw anyway, since you use 4 backing plate screws to adjust. I am of the opinion of indicating the back portion of the barrel where the chamber is, and let the muzzle be wherever it needs to be. What Clark shows using the copper wire to allow the barrel to be stress free is the right way to go. I reach way inside and indicate where the throat is, then go from there.

But, like I said, many ways to skin this cat.

Wayne,
Like you, I made a 4 jaw spider. picture of a 4 jaw spider, please excuse non mathing bolts



I have too hard a time centering with 3 jaws at 120 degrees.
I copied RoyB's picture, mostly, but I had to make mine a 4 jaw.

Wayne,
I just went to using a setup that is exactly as you describe and I love it. It's sometimes scary to watch the muzzle end of the barrel if it's a light sporter weight but I feel that dialing in the chamber end to perfection is the way to go. I have used this method on the last three I have done and am delighted with the results. I dial in two places on an indicator rod to zero. I also use one of Greg Tannels reamer holders which I feel is one of the best out there. I feel that this method is not only more accurate but a helluva lot faster to set up then trying to dial in both ends. IMHO Jim

I use a 4 jaw and a spider with the barrel through the headstock as well. I run indicators on the front and back of the barrel at the same time until the chamber end is within .0002 and the muzzle end is within .0005 (when working on the chamber end).

Jim, it has worked well for me. I also aligned the spider on the left with the 4jaw. I place my indicator at the 3oclock position on the pins, and adjust fore and aft accordingly.