Run out ?

Josh Cox · Post by **Josh Cox** » Tue Aug 05, 2014 3:47 pm

Last Saturday I had the great fortune of shooting at the Herberton OPM, I won a prize, which turns out to be one of Peter Smiths awesome run out / case thickness gauges.

Have been quite particular when seating my projectiles to half seat them, raise the handle a bit, twist the case and then fully seat, to try and reduce potential run out.

Now with my new run out gauge I am seeing about 2-4 thou run out in my loaded ammunition, what is the general consensus on what is acceptable ?

A big thanks to Pete Smith for such an awesome prize.

Post by **AlanF** » Tue Aug 05, 2014 6:29 pm

Josh,

While I would probably hope to get it better than that, I don't believe it would be a problem, unless you're running very little clearance around the neck (say less than 0.002). FL sizing also means you can get away with more runout (which is fortunate because it is often the cause of runout).

Alan

KHGS · Post by **KHGS** » Tue Aug 05, 2014 10:39 pm

Josh,
Runout is something that we should try to avoid, having said that I think it's importance is somewhat overstated. What you are achieving is in my opinion within the acceptable range.
My .280HI is formed from necked down 30/06 brass & fireformed to Ackley configuration, the loaded cartridge prior to fireforming will have runout up to .010" & will regularly shoot 60's at the shorter ranges in 2 different barrels, neck clearance is .002" with Lapua brass. Makes you wonder doesn't it? As I have said before many times, the more you learn the less you know!

Keith H.

John23 · Post by **John23** » Wed Aug 06, 2014 7:17 am

I have been experiencing similar run out to Josh with my 308 (that I bought from Josh )

Is the simplest solution to run out a guided comp seating die?

I have been using a standard rcbs with this rifle and I am left wondering if this is where my problem is coming from as I never had this issue when using my forster ultraseater with another cartridge.

I am sizing with a redding neck bushing die

JH

pjifl · Post by **pjifl** » Wed Aug 06, 2014 8:00 am

I always aim for less than 0.002 inch runout and my loading reliably attained this or better.

About 1 year ago I changed something without thinking and assumed the runout remained low. In reality, there was the occasional cartridge with 0.010 runout and quite a few over 0.005.

When I noticed and corrected the problem, occasional flyers seemed to disappear and my shooting improved.

I do not know where to draw the line, and it may be that in TR shooting you have more allowable tolerance. But I do think that I was non competitive at a few major shoots because of this. You only need one or two flyers over a few days now to be out of the running.

I always now check a random selection for runout in EVERY box.

Peter Smith.

ShaneG · Post by **ShaneG** » Wed Aug 06, 2014 1:36 pm

Did a test on my equipment with Dave Mc a few weeks ago.
I have similar run out - around .003
We determined that the
Redding neck bushing die was the culprit!
Causing .0025 variation due to clearance on die body and same in bushing area.
My loads normally shoot quite well but I really would like to reduce same.
It is a matter of the lucky lottery with most factory dies.
Similar results from a Wilson die in arbor press.

Brad Y · Post by **Brad Y** » Wed Aug 06, 2014 3:46 pm

Try a redding body die to bump shoulders then a lee collet die for the neck. Wish they made them in the 284

jcinsa · Post by **jcinsa** » Wed Aug 06, 2014 3:55 pm

Id love to see a picture of one of Peter's runout gauge.

Please could someone post one.

Thanks in advance

John

Josh Cox · Post by **Josh Cox** » Wed Aug 06, 2014 6:06 pm

DannyS · Post by **DannyS** » Wed Aug 06, 2014 9:23 pm

Dave Mc and Peter Smith, can you guys move to Western Victorian, please. Need your advice locally

Cheers
Danny

Josh Cox · Post by **Josh Cox** » Thu Aug 07, 2014 7:39 am

Stop brown nosing Danny, they're ours and we are not sharing

Post by **AlanF** » Thu Aug 07, 2014 9:07 am

The Yanks got a few rocket scientists out of Nazi Germany, so why not? However eastern Victoria is where its all happening

.

Bindi2 · Post by **Bindi2** » Thu Aug 07, 2014 9:20 am

For real innovation and progress the wild WEST is where you need to look.

johnk · Post by **johnk** » Thu Aug 07, 2014 2:30 pm

Don't know how any of you buggers can see with your heads where they are. :roll:

Howard · Post by **Howard** » Thu Aug 07, 2014 3:10 pm

I have a question about this runout you blokes are talking about.
Is it the "angle" that the bullet is sitting in the case, compared to the line of the bore? That is, the tip runs out, but the base does not.
Or, is it the "offset" of a bore aligned bullet, to the bore. That is, both tip and base run out in unison.
The latter may be caused by a case neck with differing thickness on each side?
A bullet that has runout of .010 or more, would surely align itself to the tolererances of the chamber? I would think it would come back to the tolererance or difference between the bullet diameter and the throat diameter, assuming that a pre-fired case is a snug fit in the chamber.
I can't see that diameter difference being .010, but just what it really is, I don't know.
I agree with Pete that the correction should be in the loading dies.
Howard.