Years ago, John Taylor did a mathamatical thing called knock out value. He used the bullet weight times diameter times velocity then deivided by 7000. That would give you a number such as the 7mm mag of 21, the 243 at 13 30-06 was 22 or something like that. This formula would give you an idea of how truly owerful a cartridge was / is. A big fat weighty bullet would be the winner everytime.

Reality is this though, create a sucking chest wound, the animal goes down, lose enough blood, the brain dies, and the meat is yours.