Rechamber ruger 77 from 458 win to 458 Lott

Discussion in 'Gunsmithing' started by reinwood, Oct 23, 2008.

  1. reinwood

    reinwood Member

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    Hi,

    Does anyone know if it is possible to rechamber a standard ruger 77 in 458 Win int o a 458 Lott?
    I wonder about the action/magazin length.


    Thx.
     
  2. James Jones

    James Jones Well-Known Member

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    It should be a relitivly easy job , the 458 Win is a pretty short case considering it rank in the mag class and I've seen 77's chambered in 375 H&H so the Lott case should be no trouble.

    If I'm not mistaken the 458 Lott is just a bit longer than the 458 Win with a weee bit less body taper , if this is true then simply running a 458 Lott reamer in their should work and the barrel would not have to be set back. I have been told by several guys that yu can safely shoot 458 Win ammo in a 458 Lott though I have never had the chance to compair the two cases side by side
     

  3. reinwood

    reinwood Member

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    The case is 3/8" longer. 3/8" making 300fps difference !

    I think you are right the rechamber is easy.

    What I do not know is if Ruger is using the same action and magasin for the model in 458 Win and the models in 375HH or 458 Lott.

    If the answer is yes, then the conversion is easy and cheep
    If the answer is no, then remains to be checked if the action and magazin are long enough to deal with the 3/8" longer ammo.
     
  4. James Jones

    James Jones Well-Known Member

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    I'm pretty sure that Ruger (like most others) only has two size actions , Long and Short.
     
  5. GLZ

    GLZ Well-Known Member

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    Aug 22, 2008
    Ruger has 2 action lengths in thier standard 77's, The factory 375 H&H, 458 Lott's are built on the RSM (Ruger Safrai Magnum) action. This action is much larger than the standard 77 MKI and 77MKII. Most of the 458 Win. Mags I have seen have been on the MKI with tang safety. The rechamber is straightforward, the mag box, rails and action must be opened up to use the Lott. It can be done but will not be cheap. A guy over on accuratereloading.com did one several years ago and I am sure many others have.
     
  6. Dirtyharry77

    Dirtyharry77 Member

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    The case length on the .458 Lott is three tenths (.3) of an inch longer than the .458 Winchester Magnum. The conversion is relatively easy for any competent gunsmith. Both the Lott and the Winchester Magnum cartridges are based on the .375 H&H magnum case. And yes, if you can't find the Lott cartridge you can still fire your old Winchester shells in your modified ax.

    Now go 'one shot' old Mr. M'bogo...