I always was told the distance to shoot was the distance you can hit a 6 inch "desert" sized paper plate, you know, the kind the women's auxiliary puts the cake on. Those stapled to plaster lath's stuck in the ground at varying distances are a very good approximation of the kill zone on an average sized deer.
I have killed a few deer with a 4 5/8's blackhawk. most were really close, the ones that snuck up behind me in a stand. I have killed several with a .45 colt in a trapper, a real one, with the 14 inch barrel. and its lightning.
Daughter and I have killed U.P. black bear as well with the trapper, and I have shot hogs with the blackhawk, I now have a redhawk in .45 colt that I am working on some warm loads for. I use the LBT style bullets, hard cast, and they kill a good sized feral/mix hog with ease.