Well, last night I loaded some 308 ammo: 165BalTip, 44grs of 4064, and 210Match primer. I loaded these using my Lee collet dies. Measured run out was less than .002 max to min. I plan to shoot these in my .308 custom against Rem factory 150's that were not tight, ie, they ran .005-6.

I will run the test, but what should my range be? We have 100,200, and 300yds. I think that the longer range will be telling particularly because the rifle is pretty good. Feed back please. Ku-dude

Personally, you know I've been begging for someone who's a good shooter with a good gun to do this. I'd like to see 300 yds as a quarter inch or 1/2" at 100 yds is meaningless to a hunting situation.
BUT--It sounds to me like you used different dies and to me that might ruin the test. It's hard to argue the consistant neck tension (albeit light neck tension) of a collet die. My thinking is it would be great to use the same die with the same lot of brass to get consistant neck tension as I think this has as much to do with the potential accuracy as runnout.

BUT--why not give it a try any how. MANY THANKS FOR THE TIME AN EFFORT OF ANY TRIAL we all do and the info we share with one another.

At 100 yards it's not likely you will see very much difference. Where the difference in runout starts showing is in ranges beyond 300 yards, preferably 600 yards, particularly in a hunting rifle. With their ability and their supertuned equipment, the benchrest shooters can tell the difference, as can a good and experienced shooter, at the shorter ranges, but for us average folk, the longer ranges will clearly show the differences.

I'm not trying to be too critical here, but there are simply too many variables between your two test groups to render any meaningful information about the effects of runout on accuracy. Any accuracy differences between the two loads could indeed be due to differences in measured runout. It could also be due to one or more of the following: type of powder, powder charge, type of primer, seating depth, neck tension, different bullets, different pressures, different velocities, different cases, etc...

About the only thing this will tell you is which load is more accurate in your rifle. It will give you no indication of why one load is more accurate than the other.

If you want to solely test the effects of runout, you'd have to use the same brand and lot# of cases, the same brand and lot# of powder, the same brand and lot # of primers, and the same brand of bullets. Sort the loaded cartridges by amount of measured runout, and then fire several (at least ten) groups using the lowest measured runout cartridges vs several groups of the highest measured runout cartridges. All groups fired under identical atmospheric circumstances, of course.

My suspicion is that at hunting ranges (< 400 yards) with fairly stock hunting rifles, there isn't enough of a difference in group sizes to matter much. Most factory rifles aren't very square, so even if the cartridge has zero measured runout, the bullet will still be at an angle when it hits the lands, thereby inducing yaw into it's rotation.

[ 02-27-2003, 02:32: Message edited by: Norm ]

What I hear you saying is the runout challenged bullets need to be as close tothe same as those I loaded as can be. I cannot do that and use the same dies. I can try to load up some with the same formula and use my regular dies. I can only hope that there will be some difference in run out. (My regular loads run between the Lee collet dies and the Remington baddies.)

The distance will have to be 300yds because that is the length of our longest rifle range. The rilfe is a custom Mauser which is a sub-MOA rifle with the stated load. Ku-dude

PS: I did not say I was a good shot. But I'll be the same gunner on both batches.

I agree with Bob...I never had any particular problems with .308 match ammo with excessive runout at 100, 200 and 300 yards. At 600 I'd worry about it in the course of match fire but in all honesty I used the loads with excessive runout for practice and they shot just as well. Where I did notice significant dispersion with bullets found to have excessive runout was at 1,000 yards.
Mind you I'm speaking in terms of highpower match accuracy which is very different than benchrest accuracy. At 100, 200, 300 and 600 yards I can hold a rifle to about 1.5 MOA, prone unsupported. And just about any round, runout or not, could be expected to group within my ability to hold the rifle. That didn't hold true at 1,000 yards.