The BC of the 77 TMK is .420. Not as high as the 75Amax at .435 or the 80 amax at .473 but it should work. I'l test the SMKs but as long as the Amaxs are grouping under 1/4" I'll stick with them.
I've seen a lot of posts from people saying the BHW barrels don't shoot the solid copper bullets like Barnes and the Hornady GMX very well, have you tried any or have a guess as to why they don't?

Last edited by constructor; 04/23/15.
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