I've taken several whitetail does and a small buck with the .45LC.
Shooting a Colt's New Frontier.
Load is a 255 grain LSWC over 20 grains of 4227, for probably right about 1000 fps.
None of the deer went 30 yards.
I've shot more w/handguns than w/rifles. 10mm, 41 mag (3 screw), 44 mag, 45 Colt, & an FA 454. The Bisley 45 is my favorite. Don't hesitate to use your carbine. Those of us that use archery still manage.
I killed a buck and a doe with my Henry 45 Colt back in November. I load my own, 23.0gr Accurate #9 with 250gr Hornady XTP. The doe was shot at about 60 yards, and managed to run about 50 before she went down, even with a perfect heart shot. The buck was shot at about 30 yards, and he went about 25-30 yards before he went down. I'll be using it again next fall.