slg-
I'm assuming that because you're building, you're putting the metal in a quality stock with correct LOP - as you're likely aware, that makes a HUGE difference. I don't like getting banged around any more than the next guy, but I think the 270wizzum is a puttytat to shoot. While you might not notice the noise in hunting situations, you're slowly accruing some incremental hearing loss. Still, if you think you need a brake on it, have at 'er - just please stay downwind of me at the range.