At the risk of sounding trite, hunting results are about 95% bullet placement, and 5% bullet power and construction. My grandfather shot 50 large BC moose with a 30-30. Only one was not a one shot kill.
The 270 is very powerful. A boiler room hit would be 100% effective on anything in North America. I once expressed concern about a buddy using 130 gr bullets on moose. He said "It blows their lungs out their nose." My theory vs his experience.
One of the things you will learn with hunting experience is to think 3D so your shot goes through the boiler room, and to wait for a good shot.
Practice enough with your rifle from the standing and sitting position so you know your capabilities. When sitting, practice shooting off both shoulders. An animal approaching you from the right or right rear has to be engaged from the left shoulder if you want to reduce excess movement.