[Kerf]

I’ve gotten into the habit of indexing my center fire rifle rounds after reloading. I find the high point on a run out tool and use a magic marker on the case head to indicate the high point and then load them in to the gun a twelve o’clock using that mark. It tightens up the groups good.

And, now for the real question. Has anyone done any experiments with rim fires? I’m thinking of building a device to measure the run out on rim fire cartridges, so they could be indexed the same way as center fire. Or, has this been tried before and I shouldn’t waist my time reinventing the wheel? Or, in the grand scheme of things rim fire, it doesn’t really matter??

What say you?

[cdrt]

Gill Hebard carried a device that would measure the thickness of the rim on a .22. Is that sort of the same thing? He still has it in his current catalog.

[enfield]

I'm not sure that rim thickness, or variations in it, would contribute to TIR.

[Jim Watson]

I am not a serious rimfire shooter but know a few.
These days they seem to attach more importance to sorting ammo by weight than by rim thickness.
There is also a "sizing die." From the description at
http://rimfireshooting.com/index.php?showtopic=1877&hl=sizing+die
it sounds like a bump die that increases bullet diameter at the expense of OAL.

If you want to test for indexing, shoot the gun, not the keyboard.

[Kerf]

I think I'll take Jim's advice and try it out. Let you know how things develop.

I've tried sorting by rim thickness, and that seems to improve groups a bit. Separating by weight hasn't seemed to matter much. And, I've tried the Pace Kelly device for squishing the bullets, which did make the groups better. Only problem with that is in most competition, you can only used unaltered factory ammunition. So, I was thinking if there is some way of indexing the rounds…. Guess I’ll just have to try’er out.

Thanks for the advice

Kerf