I have 6ppc,.262nk,new lapua brass,fed primers,65gr v-max,loaded rounds measure .259,h322 26gr, bullets jammed/shoulders bumped/lightly lubed.The first 5 went smooth and the next few wasn't that bad but I could tell a differnce.I looked at the back of the brass and it was real shiney around the primer pockets.I mic the hard brass with a harrells bushing at 1.556 and the others was 1.554.I tried some new norma brass and it went perfect so, I don't know whats going on with the lapua brass.