300 blackout is the main caliber we use to shoot deer at our place. I either use the tnt 125gr bullet (solid copper, etched so it breaks apart on impact) or the Tac TX black tips. We load to about 2250 fps which gets you around 1200 ft lbs of energy. Cleared all the load data with our game wardens for our unit. Works really well, most deer only make it about 20 yards. We have people use ours when they hunt here so we don't have any ricochets. Still is a through and through, but dumps most energy into the deer. No recoil and sub moa at least to 150 yards which most of our shots are, um, 30-50 yards... Hunting up in the mountains would be different, I would probably opt for more range and power than the blackout.

Like SAFriday said, almost the same ballistics as a 30-30. I think I saw a stat (could just be bullshit) that 30-30's have killed more deer than all other calibers combined. Could be cause they been around forever. Plus none of my 30-30's are threaded for cans.

Also for Colorado a pistol is ok to use for hunting, but not an sbr. Can't use a full auto trigger either, WTF? I have asked both questions to the wardens. Suppressors also are OK for hunting in CO.