I got time to work on the Non-Ruger 10-22.
It had an issue with groups that were sometimes 0.3″ and sometimes 4 inches.
I took it out of the stock and found the barrel screws had come loose (despite using blue Loctite). Once tightened and re-assembled, I took it to the range and re-sighted the scope.
55 rounds in groups of 5, none larger than 0.6 inches….much of that was me, not the rifle.
I think I fixed it.