Battzilla

I was looking at the PRI MK12 Mod 0 upper and there is also a 1:8 version.

I know 1:7 was the original twist, but I was curious how MK262 would perform out of either rifling at 500 yards (1:8 vs 1:7)

I looked at the Hornady ballistics calculator, and it's showing the same ballistics. (im sure this is incorrect)

Curious about hearing people's experience shooting heavier loads (70-77gr) in the 1:8. Is there a big drop off towards further range? Do the groupings open up?