I have a butt pad that is an 1 3/8" thick on a 300 RUM with a heavy scope and brake. The thing kicks pretty good, but there really isn't a pain issue as the pad is fairly soft and absorbs the recoil. I think the pad is compressing quite a bit more than any of my harder pads which in turn is allowing more backwards movement with the gun. If everything else on the gun is good, is there a possibility this extra movement is contributing to some erratic groups?