looking for insight on loads and best components (bullet selection, powder, etc) for my 20" 1:10 heavy barrel. I have recently added a precision armament brake. I have worked out the harmonics. Now I am just trying to find the right mix but am having some frustrations. No expectations on shooting beyond 600 with this rifle but want solid performance at that range. Anyone have suggestions? SMK 175 and ScenarL 175 are on my bench. Was considering 155s for the speed but drift is a big question mark. Open for suggestions....