So an update to this situation: Barnaul ammo is actually just that terrible.
I bought 3 other brands to try out; Federal American Eagle, Winchester white box, and CCI Blazer Brass. All 3 of them shot slightly left, which could just be me, but that's also easily fixable because the sights are windage adjustable. Of the 3, Winchester shot slightly low, maybe 1-2 inches, with a standard sight picture. The American Eagle stuff shot more or less point of aim, but the CCI stuff was the most accurate, shooting pretty much exactly point of aim in terms of drop each time. After having shot all of these I went back and shot the Barnaul and, once again, it shot a good 6" low. I had some other people shoot it with the Barnaul and they all also shot a good 6" low.
So moral of the story is, Barnaul ammo doesn't shoot well out of these guns. Frankly I'm astounded that there's that much of a difference, considering they're all 95gr FMJs.
Thanks for the update, great post!