Really suprised nobody has brought this up. It ALWAYS does on any hunting forum Ive ever been on. Sooooo here we go........................ I will start by pointing out many States/Countrys have rules that limit "or not" what size projectile may be used to take Deer. And lets for now limit it to WhiteTail (or an equivliant i.e. in Australia) as its the perdominant species the Majority on here hunt. I will give my thoughts first. In Missouri its ANY CENTERFIRE cartridge.... No FMJ. Thats (as far as I know) .18 Bee - .50 BMG. Shotguns its .410 and up with slugs only. Black Powder is .40 cal for the minimun. Handguns is centerfire again and black Powder handguns .40 cal. And the best is......In my opinion..... Any of the above. Reason....Its bullet placement that counts. If you have one that you think is better, other than you just like it, and we all have our favorites, ........why is it better than the rest.