Loaded Round Concentricity questions

dthunter

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My rounds usually average 0.003" or less out of concentric. Measured from about .125" from the case mouth, and on the bullet major diameter. Out of 20 rounds I typically get 3-5 rounds that are 0.003" out. Some say that these rounds will not shoot as accurately. I havent found that "YET". Maybe I have been lucky. I have shot out to 1760yds. with these rounds and they shoot sub-m.o.a. consistantly. How much difference do you guys think it would make if all the rounds are within 0.001 or less"? hope you guys have some thoughts on this. Have fun, and straight shoot'in!
 
It is my understanding that rounds out by .003" or less can not be shown to be inaccurate out to 1000 meters. I personally load match rounds in bulk and then sort for concentricity. Anything under .002" I use for match and .002 - .003" I use for practice and winter leaque shooting. Anything over goes into a separate pile for barrel breakin. If those rounds are reloaded and again show over .003" I throw them away because they probably have case wall thickness issues. Steve
 
Benchrest rifles chambered in Benchrest calibers may be capable of determining a difference in accuracy between rounds with 3 thou run out and rounds with 0 run out but I doubt a Precision rifle will notice it.
 
Concentricity or runout

We all strive for the perfect loaded round, normally that doesn't happen so we're left with some runout. Now picture this, the round is loaded long, say 0.010 so it JAMS into the lands, at this point I'm guessing that 0.003 runout is gone or at least won't make any difference to the accuracy of the group shot. If it's long range the real variables are conditions at the time of your relay and the shooter.
Enjoy.
 
Mr Berger himself once said .004 or less is good to go.
I try to keep the loaded rounds at .002 thous. Any more than .004 thous. I will re-seat the bullet. if that doesn't do it, I'll check the case. luckily I don't have to do that very often. I think proper sizing is the key to reduce run out.
 
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I keep my rounds .004 or less, if more I will use the neco device to adjust,if they will not adjust they get marked for practice or blow off.
I have shot lots of 1000 yard matches with these tolerances and have never had an issue
 
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