McMillan won't make an Edge stock for Ruger 77's. The design of the recoil lug leaves too little material behind it so the stock wouldn't be strong enough.

At least that was their story a while ago, I don't see that info on their newer web site but have no reason to think they've changed that policy since they still don't recommend an Edge for anything more powerful than a .300 WM in any rifle.

Gunnery, gunnery, gunnery.
Hit the target, all else is twaddle!