I got bored and took the 375 Ruger out for some practice today. I have a pile of 300gr Sierra GameKings so I loaded some up with a case full of H4350 to see how they'd shoot. Got it zeroed at 100 yards and went straight to 568 yards just for fun. First shot was on the left edge of the target rock, but that was all my fault.
The rock is probably 12-13" across, so it's a pretty good size target. I'm pretty happy with the 3 shots before I adjusted the hold though especially for shooting sitting off of the sticks. It took 14 MOA to hit at 568 yards, so the drops actually track very close to a 308 with a 175 SMK. Next trip out I'll see about going to 750+ yards.
Anybody else do any long range shooting with unconventional guns or chamberings?