When it's green out, I usually use the old single shot, Harrington & Richardson Topper model #58 in 410, but when it's brown out, I use my suppressed RAR in 300 BO, with a subsonic 130gn Speer Hot Core load I developed, goin 790 FPS. This along with a Vortex 4-16 Diamondback scope produces head shots to about 50 yards very easily, with very little to no hold over.
The expansion velocity on this projectile is waaaaay above the MV produced, and does NOT expand, but instead pencils through, so meat damage is minimal with proper shot placement. Head shots produce a helicopter effect flying squirrel, and very few (none) are not recovered.
I hunt in a very secluded, sparsely populated area, and take only low angle shots, as the Hot Core keeps on a'goin after deliverin its near head removing punch.