I have a custom built 260 tactical - 260 rem with a deeper throat to seat 140 gr berger vlds... 1:8 twist - 27 or 28 inch barrel..? I forget. I'm shooting 41 grs of H4350 right now that gives me the best groups.... Yet it is not as consistant as I want with grouping, and it will not shoot under a half inch every single time.. time after time... I've gotten some good groups with it, I know it will shoot, I'm just not getting the results I want with H4350... Any Ideas on another powder to test out to see if it likes it any better?