Update: I made it out to the range today with the ammo I had left from the match and implemented the suggestions I received; namely getting my scope set up properly and keeping my left elbow planted by loading without dismounting the rifle and dropping the bolt by reaching through. I'm happy to say it made quite a difference.
Since I was doing some remedial work, I only shot SR-1 targets at 100 yards. Also, I mentioned our range isn't set up for prone shooting, but I discovered I'm able to lay on a table (with my feet hanging off the back). It's not ideal, but far better than nothing. Anyhow, I finished up with a 199-5x. The lone 9 was a called oopsie (somehow managed to break the shot while I was still settling
). I'm still hitting a bit high, and not sure why, even though I lowered the sight 4 clicks (2MOA), which is why I only got 5x. I know it wouldn't be the same score on a proper slow prone target, but it's definitely progress.