...So I bought a bushing die with the right size bushings with the plan experiment with neck tension to see if I could wring a little more out of my 300wsm. I turn my necks and had been FL sizing with about .0015 for neck tension. This combination always yields a total run-out of less than a .001
So I start with the bushing die, check run-out on fired case, about .0005, resize case and check run-out again,.0000, I'm thinking this is going to be good. I seat the bullet and check the run-out and it is .002
Nothing I do changes anything, its always .002 of run-out after I seat the bullet. I can take the same case and FL size it and and seat the same bullet and get zero run-out or very close to it. The only thing I can think of is that some how the way a bushing die does not size to the neck/shoulder junction is somehow messing it up but that's just a guess.
Am I missing something?
So I start with the bushing die, check run-out on fired case, about .0005, resize case and check run-out again,.0000, I'm thinking this is going to be good. I seat the bullet and check the run-out and it is .002
Nothing I do changes anything, its always .002 of run-out after I seat the bullet. I can take the same case and FL size it and and seat the same bullet and get zero run-out or very close to it. The only thing I can think of is that some how the way a bushing die does not size to the neck/shoulder junction is somehow messing it up but that's just a guess.
Am I missing something?