My dad is shooting Hornady 150 gr SST.277 bullets in his 270 WSM. They have blown up 3 times out of three animals this year. All died quick, but he would like to eliminate this exloding performance.

What bullet will not explode in <100 yard shots and has a hard tip to prevent magazine damage? He would like this for game from Antelope to Elk. Shots are typically 0 - 500 yards max.