I am reloading for a 30-06 old rifle and a 7MM RM new rifle, both Reminton 700's. This is the neck turning stage. I have used a Redding neck checker and will be neck turning the brass that has more than a 0.0015 variance. Both calibers case walls at neck are between .011-.016 thick. So if I turn to .012 to remove the variance (less than .0015) the following circumstance is: .307 = bullet OD .012 = case wall thickness side 1 .012 = case wall thickness side 2 .331 = reloaded bullet at neck +.002 = clearance to chamber wall (x2, .001 each side) .333 bullet + clearance to chamber wall wanted .3406 = chamber measurement -.3330 = bullet + clearance to chamber wall wanted .0076 = excess clearance to chamber wall ??? Both the 30-06 & 7MM have near the same ".0076 = excess clearance". How will this "excess clearance" effect my accuracy? Do I need a new barrel or thicker brass? Or do I need to worry about the .0086 clearance for long range shooting as defined up to 1000yards?