I have bought a Mossberg mpv predator in .233. What I need help with is what grain bullet should this rifle shoot well? I have shot 55 grains and 62 grain bullets through it and so far it seems to like the 62 better. It has a 1:9 twist and a 20 inch barrel. Does the 1:9 twist supposed to shoot the heavier bullets better or the lighter ones? I appreciate any help you folks can send my way. Thanks, Travis