I cleaned the rifle thoroughly, and torqued the bolts according to spec. Did a ladder test from 87 to 93gr with retumbo today. Best group was still only 1.1" at 100 yards.
Can excessive jump with the hybrid bergers be the cause? I use this rifle for hunting so do not want to go over mag length, consequently they are jumping .138". If I stretch them out just shy of the mag lips, I can reduce it to .105" however that still seems rather excessive. My 250 SMK's I am loading at 3.68 only jump .020"
Seat a few longer for singles and find out. No other real answer. Yes it could very possibly be a huge difference.