For those interested:

http://riflemansjournal.blogsp...ting-die-runout.html

That was a good read. I would have expected the Wilson to place first. I wonder if the press which the screw in types were used in had any influence. Will continue with my Wilsons all the same.

Von Gruff.

I ran a test on 60 some fired Winchester .308 cases years ago. All cases had their necks previously turned to a bit over .013 inch before firing. A third were neck only sized in a Neil Jones neck sizing die with a .333 bushing. Another third were full length sized in a standard RCBS die with its neck lapped out to .333 inch; no expander ball used. And the last third sized with a conventional RCBS full length sizing die with a .3080 expander ball.

All the sized cases were spun on a runout tool to check neck runout. Support points were a V at the back on the pressure ring and another V at about midpoint on the shoulder. I was checking runoug on the mean case axis as it would fit the chamber when fired; jammed hard into the chamber shoulder by the firing pin's impact and the back end pressed to the top of the chamber by the extractor.

Largest runout was with full length sized cases and the expander ball. Medium runout was with the neck only sized cases. Smallest runout was with the full length sized cases in the lapped out die.

All 60 cases had Sierra 168's seated to an OAL of 2.8 inches. Half of each die specific group had bullets seated with a conventional RCBS bullet seating die. The other half had their bullets seated with a Wilson chamber type hand bullet seater.

All 60 or so "dummy" rounds were checked for runout. In all instances, the bullets tended to align quite well with the case neck axis. Cases sized with the standard full length sizing die with an expander ball still had crooked bullets. And the straightest seated bullets were in the full length sized cases from the lapped out die. Neck only sized cases with seated bullets still had some runout.

I'm convinced that if you can resize cases and keep their necks straight, you could probably seat bullets quite straight by smacking them with a ball peen hammer.

But they don't have to have "zero" runout to shoot well. Two to three thousandths runout as measured from the shoulder forward to a tenth of an inch back from the bullet tip (.308 Win., for example) will easily shoot 1/4th MOA or better at 100 yards from a good, SAAMI chambered barrel with decent components.

Hey, that was great. At least I know I have a good seating die! Who needs to pay a s**t ton of cash when all your doing is hunting under 200yds

Bart, that was an interesting write-up. Thanks for taking the time to post that.

RE: the original seating die test. Pity the test did not include the Forster seater. Although, likely it would have finished on par with the Redding Competition seater - which is really a copy of the Forster with its sliding, caliber specific sleeve. The Redding is better finished than the Forster, but also quite a bit more expensive.

- mike

quote:

Originally posted by mho:
Bart, that was an interesting write-up. Thanks for taking the time to post that.

RE: the original seating die test. Pity the test did not include the Forster seater. Although, likely it would have finished on par with the Redding Competition seater - which is really a copy of the Forster with its sliding, caliber specific sleeve. The Redding is better finished than the Forster, but also quite a bit more expensive.

- mike

Thought one bought the other out....maybe I m mistaken.....so much good and bad info out there.

quote:

Originally posted by James Kain:
Thought one bought the other out....maybe I m mistaken.....so much good and bad info out there.

Could be wrong, but I don't think so. Forster and Redding should still be separate companies.

I *heard* (but I'm hardly a reliable source, so take it for what it's worth), that Forster's patent on the seater ran out, and Redding liked the idea enough to start making a copy. FWIW...

- mike

Good read but, as the author states his findings are not conclusive.

quote:

Read this article for what it is: a brief test using the dies that I happened to have and which shows a way to test rather than producing any absolute results. This is a limited, hobby time test which I conducted for my own information an entertainment.

It would be interesting to see this test repeted by a few others with their dies and see how the results stack up. I also wonder how much runout was induced by the mating of the various seater cups and bullet ogive. I`ve seen a few dies that just flat don`t like some sharp tipped (plastic) bullets, but seat everyday soft points very well.