I had Dennis Adams put a Harrels tactical brake on my factory Win 70, I can now punch 0.5 " groups and shoot a half day at the range with it, I shoot 190's with various powders as I am still dialing it in. I really like this wsm round, I like the mag so much I ordered a 300 WM 28 " bull barrel cut for a FTE badger brake, want to get the heavies moving a bit faster. The WSM with brake is like shooting a light loaded 06 round. I will tell you about the WM in a few weeks. When I finish burning out the wsm barrel I will go with a heavier contour , probably a rem varmint contour with the Harrels brake. I am really getting to know this wsm round since putting the brake on it and I like it a lot.
I agree wih Cotton above, when I shoot the WM as it sits now with the sporter barrel its shoots 0.5 " groups but even in a heavy Choate tactical stock it beats me up pretty good. Cant wait til that bull barrel shows up.