Home Forums Reloading Big Game Rifles Runout after bullet seating

You use much Lapua brass pard?

Pay attention to many of my posts? I've got about 2,000 pieces of it on my shelf, using it for hunting, F-T/R, and PRS.

Have you taken a ball mic to many pieces? Or turned many pieces?

I've used it in 308 for almost twenty years. It has been very good stuff, but not perfect. I did get a batch a while back that shouldn't have left the factory door by Lapua standards, though it was still better than a lot of mass market stuff.

Everything is assumed defective until proven otherwise.

Yes. I borrowed a friends runout dial indicator gauge from a friend. RCBS I believe. I measured one batch of ammo loaded on a single stage press vs loading progressive style on the Dillon. The Dillon is much faster, but had about 2x the runout compared to the RCBS rock chucker press.

I've also measured loaded ammo on the single stage loaded seating in one motion vs the described stepped method. The stepped method reduces runout some, maybe. 002 - .003". All depends on what I'm doing if I'm being more careful or not

If you can reduce runout by .003", and that's a 50% reduction per your prior post, then there's a problem somewhere. I call assembled rounds with .006" bananas.

That's not the comparison I asked about.

Same dies? Same processes? Did you spot check or check every single round?

World champions loading precision ammo on a Dillon...

Sometimes this forum really sucks, and I see why many don't join in.

My main point is that I have reduced runout by using a stepped seating/turn-the-cartridge method. Requires slightly more care, and I measured enough loaded rounds to notice a reduction in runout. Your results will vary.

I'm a hunter Sometimes, a target shooter most of the time, and I've never completed in a match. I've had friends say I should, but probably too busy with other endeavors.

The method described is an easy way to reduce runout.

The thing is, I've chased runout for a good while and haven't found that method to be of much benefit in my own experience and tests.

I have some dies that will seat straight w/o rotating - mostly Forster BR dies. On other dies (mostly RCBS), sometimes the 180 rotation helps, sometimes not. You only know by checking with a concentricity gauge.

OP, here. Lots of good suggestions; I'm trying to digest a good amount of it. A little more information. I'm using a Forster Coax press, and use the same reloading brands (i.e., Redding body, Lee neck, and Forster Micro-seater) for two other calibers. I'm only getting the seating runout with my .308.

Of the 200 or so pieces of Lapua .308 brass, I checked the runout on 30 pieces. Only two exceeded .001 variation. I measured the thickness on the 30 pieces and 23 were less than .001, with the remainder less than .015. I'm not running compressed loads on this one. I loaded 25 and found six that were between .005 and .009. The remainder were less than .002. I'm measuring about halfway between the case mouth and the ogive. Since I have very good luck with the Forster seating die in my other calibers, I'm beginning to suspect something is amiss with my .308 seater. Maybe I'll borrow a friends seater die to see what that produces.

For rounds that exceed .002, I just straighten them out with my homemade straightener until they're less than that. I'm not one to chase runout too much, as the rifle shoots extremely well with my straightened rounds. Perhaps this is an exercise in just wanting to know the answer due to OCD. .......or control issues?

If that works, your die is junk.

That's the best use of a runout gauge: finding ways to improve your process.

Can always try an oring on your seating die. This allows the die to self-align itself (slightly) to the case that is being sized. This and doing 2nd turn when seating has seem to help mine.