This will seem elementary to most, and I think i know, but need assurance.
So, I am threading the muzzle for a suppressor on one of my older AR’s that didn’t come threaded. Doing the work is no problem, but indicating it is. I have a spider on the outboard side, and the four jaw with some aluminum shims on the other. I used the Gordy or Grizzly rod with a bushing that has a really good no play slip fit. I indicated the last 2” of the barrel within .0003” with the rod, by moving it in and out with the tail stock. The question I have is that when pulling the rod in and out, the indicated reading is .003” different between the two inches, I am thinking this is ok, since both points were indicated concentric to the center of the spindle bore, and there is just some variation in the rod or something. Is this normal or ok for this?
So, I am threading the muzzle for a suppressor on one of my older AR’s that didn’t come threaded. Doing the work is no problem, but indicating it is. I have a spider on the outboard side, and the four jaw with some aluminum shims on the other. I used the Gordy or Grizzly rod with a bushing that has a really good no play slip fit. I indicated the last 2” of the barrel within .0003” with the rod, by moving it in and out with the tail stock. The question I have is that when pulling the rod in and out, the indicated reading is .003” different between the two inches, I am thinking this is ok, since both points were indicated concentric to the center of the spindle bore, and there is just some variation in the rod or something. Is this normal or ok for this?