Within a week I will answer this question myself for my specific situation but wanted to here the experiences of others too. My question is; does non-concentric ammo have an effect on the ES of a given load? I just got a concentricity gauge and checked some loaded ammo. Holy Moly is it crooked! Check some fired brass, as well as brass I ran through the new LEE collet neck sizer I got and looks OK. Man the stuff I loaded prior is bad though.