It must always be remembered that bullet selection is crucial when you're shooting the high-velocity magnums. Not all .30 cal bullets are equal, not by a long shot! Some are quite fragile compared to others. There are target shooting bullets, others that are suitable for deer/antelope and then there are tough, bonded-core/heavy jacketed bullets that are meant to hold together on tough animals.

It's not the .300's fault, just poor choice of bullet for the animal it was used on. A 200gr Swift A-Frame would have punched a 1" hole clear thru him end to end.

Most .30 cal bullets are designed to be used at '06 velocities, not 300+fps faster.