So I got some splatter targets to help me see my shots more reliably at distance. Small thing to note: they only work if your shots hit them

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Went out again this morning and after my initial fouling group at ~200 yards to check that my POI hasn't changed (I'm zeroed at 200), I moved out to 350 yards (348, by scope measurement) and I got another stunning 4 shot string at 350 yards. Why 4 shots? Well, I didn't see the first shot, misinterpreted a taped-over hole as my first shot, and clicked over a correction that wasn't needed. I couldn't see the next shot either, so I said screw it and shot the rest of the string, resulting in 4 shots right on top of each other that I could see... of course. Haha. The first shot is hiding under the top info tag, pretty much dead center but 3" high.
Seeing this glorious 1st group, right out of the gate, I excitedly clicked back over and down and all following attempts after the first glorious group were back up at my more average ~0.5MOA. Here is a sampling:
I also went out to 600 and got this group... just barely:
I couldn't see my impacts, and was guessing. After shooting 5 and seeing nothing, I decided that I was wasting ammo and time. I wasn't shooting badly, but I felt out of rhythm at this point (~50 rounds in), so I stopped.
I got a scope mounted bubble level for the rifle (I had been using a small construction one to check level at the beginning of the day) and found out that my cant keeps changing a little every shot. Maybe a degree or two at most. The bipod is attached to a sling stud, which is attached to a picatinny rail, attached to the bottom of the handguard tube. These were adapters Ruger put in the box, and the stackup allows the gun to twist a little relative to the bipod. I probably need to get something better. I'm not sure an atlas is in budget right now, so I may look for a sling stud that mounts directly to the handguard via the notches, instead of through the above mentioned stackup of adapters. This will allow me to pull the harris bipod down into place on the handguard, not a narrow picatinny rail, and it should be more secure like it is on more traditional stocks. I haven't checked the math, but I imagine the degree or two of changing cant was contributing to some of the walking I've been seeing in my groups.