Converting Ruger M77 MkII from Standard Long Action to Magnum?

Discussion in 'Gunsmithing' started by jasonprox700, Jan 14, 2010.

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  1. jasonprox700

    jasonprox700 Well-Known Member

    Jan 17, 2007
    I currently have a Ruger M77 Mark II chambered in .280. Is it possible to convert this over to a .338 WM? The reason for this is I like the gun, but I would rather have a .280 AI in a Rem 700 than in my Ruger. I want a .338 that is comfortable to carry, and this gun fits the bill.

    Besides opening up the face of the bolt, what other mods would have to be made?
  2. cornstalker

    cornstalker Well-Known Member

    Aug 13, 2008
    I don't know for sure, but I think the action length is the same. I have two short actions and a .338 WM, so I don't have a standard long action to compare with.

    I think the only mods are opening the bolt face and add a muzzle brake on the new barrel...:)

    I'd be happy to measure the mag box, ejection port, or anything else that I can on my .338 for you for comparison's sake.

    You could try PM'ing Coyboy too. He seems to know them pretty well.
  3. ForneyRider

    ForneyRider Well-Known Member

    Jan 6, 2010
    338 Win Mag and Rem 7mm Mag each have a 2.5in case and I load the 7mm out to about the same length as 270 Win, ~3.30in.