I think it is a matter of preference. An AR can kill a deer as well as a bolt action rifle, shotgun, bow, etc. The only rifle I currently own is a M4 variant of AR chambered in 5.56, so when I go hunting that is what I will be carrying. I use a 10 rd mag and my gun is pretty darn light. I bought the rifle for the purpose I like them and love shooting. I decided to give my hand at coyote hunting, but didnt see any, so I decided to explore a little. While scouting the land I had a buck walk up on me. Didnt notice me and I could have shot him, but I didnt. I was loaded with a 55 grain .223 plinking round and did not have a clear shot. He was about 20 yards from me and a shot to the vitals probably would have killed him, but I didnt try it. I now have 75 grain BTHP 5.56 rounds which should kill a deer. I also can legally hunt with an AR in Georgia. My future purpose will be another upper receiver with a bigger caliber, but right now, if I want to go hunting gotta use what I have.