The Winny F/W in 300 Win isn't grouping well because you are more than likely anticipating the recoil....I've got one in '06 and it boots like a mad mule, so I would figure yours would boot like a wizzed off whale.
Free float the barrel and see what happens. You will also need good glass. I put a cheap scope on mine and the recoil would move the cross hairs around. Then I bought a Leuplod and never looked back.