I know a guy whose boys have killed a dozen cow elk with the .250 Savage and 100-grain Nosler Partitions, and all the bullets exited. They just wait for pretty much broadside shots and put them in the right place.
I also know a woman who's killed 17 elk with 17 shots from a .257 Roberts, though none was a big bull. She also just puts a bullet in the right place and watches them fall over.