Given the same bullet construction, angle and shot distance the 300wsm probably wouldyield the same damage as it's cousin the 300wm. Is it too much .... nah, is it required....nah. Pick the right bullet for your situation and you'll be hard pressed to see much difference between a standard and magnum in terms of damageor meat loss.By picking the right bullet I mean match to the hunting conditions by taking into count the species, distance of shot you expect to shoot and point of aim.

Sounds like the 270wsm is working well for you, so why the change?