Also about groups and zero. If you zeroed or are verifying dope based off of 3-round groups that could be the bulk of the problem by itself. Zero precisely to the nearest click using a 10 or more round group, or it’s likely your zero is off a little, which isnt so noticeable at closer ranges but will compound as you get farther out. Same with verifying drops. Those two factors together—a zero that is a click or two off, and not being able tonsee the true center of your group by virtue of using smaller round-count groups, could easily create what looks like a .3mil error at 800 yards.