Have not shot a deer with a 44 spl, but have killed one with a .45 Colt 250 grain cast fn going only 850-900 fps. Busted both shoulders, all the way though and out. (close range, approx 15 yrds) I can't think of one reason why a .44 250 grain cast bullet going about the same speed would be any different at all. The .44 heavy bullets of equal weight are longer than a .45 Colt, some might say that is an advantage, but either way, same weight, same speed...same results. I have not tried the lighter faster bullets for hunting, so someone who has would need to tell us what those do to deer. I think I would agree with Mikey, 240/245 gr swc for hunting, I like the Keith style 250 grain from Mt. Baldy so far in my flattop. I'm going to try 240 grain cast I got from somewhere else as soon as I can find the time. I can say that a heavy cast bullet at moderate speed won't blow your eardrums out like a high pressure load either, and they will penetrate and break bone and keep going in a straight line.