I am not an expert by any means. I have only been fortunate enough to shoot at two cows. One shot, one kill on each. I am convinced that all the talk about magnum calibers is emotion and has little to do with reality. I agree with those guys who say that a well placed shot is the key. Bottom line... the 270 under 300 yards with the premium factory rounds being recommended will go through shoulder bone... will exit the other side and will probably shock you with the amount of damage and meat loss it will cause. I believe Magnum rounds are killing animals with the channel wounds and not depositing their full energy inside the animal as they are designed to do. Weatherby started all this by demonstrating that a small 22 sized bullet at high speed could literally explode inside an animal causing shock and collateral internal damage. With today's ballistics I actually think more and more hunters are losing and wounding animals from being over gunned, and poor shots than under gunned. My next hunt, I just want to kill the animal and eat it... not splatter a quarter of it across the country side. Don't mean no disrespect. Just sharing my situation.