Ben Meyer
40 Cal
.40 will work. But I wont use one for deer, and heres why. Most of MY shots tend to occur in the last 45 min of shooting light. I dont care WHO you are, how many deer you've taken, etc. At 5:40pm in the mid November Indiana woods, iron sights and a deer at 50 yds can be tough. Tougher the older you get. Hunting with a .50 or .54 gives you much more of a margin of error for a not PERFECT shot than a .40 ever could. More ft/lbs of energy for a pass thru, bigger hole. Not rehashing the hunting ethics, blood trailing is harder at night, so I only take shots I KNOW are kill shots, because losing a deer to coyotes SUCKS. I took a big doe at 42yds last year at 5:40 with my .50 and it worked great. Ran 30yds and flopped. I'd have thought twice about taking that one with a .40. I'd rather not have to think twice.