Will a 257 Wby Reamer Clean Up a 25-06 Chamber?

Discussion in 'Gunsmithing' started by sambo3006, Oct 28, 2013.

  1. sambo3006

    sambo3006 Well-Known Member

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    I was toying with the idea of having an Encore 25-06 barrel rechambered to 257 Wby. Obviously the barrel can not be set back so I was wondering if this can be done. Thanks!
    Sam
     
  2. Edd

    Edd Well-Known Member

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    I'm not a Gunsmith but I believe it can be done. Unless you have a custom reamer made, there will probably be more to it that just running a 257 reamer in the existing chamber. If you look at the SAAMI drawings you will see that a 25-06 has a slightly larger neck and freebore diameter than a 257 Weatherby. So without a custom reamer, you will have to ream the chamber, neck, and throat in separate operations with separate reamers.
     

  3. J E Custom

    J E Custom Well-Known Member

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    The best/simple thing to do is re chamber it to 25/06 AI. that will step it up a notch and keep the
    chamber wall close to the same. (stronger). and you should pick up 100+ ft/sec.

    J E CUSTOM
     
  4. sambo3006

    sambo3006 Well-Known Member

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    J E Custom,
    Wouldn't that result in too much head space in an Encore barrel? Plus I've got brass and dies for 257 Wby and not for 25-06 or AI.
     
  5. J E Custom

    J E Custom Well-Known Member

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    Head space would have to be set while chambering the 25/06. it will clean up and increase the chamber size.

    25/06 AI will have close (But not quite)to the same performance as the Wby and has no belt.

    Also with the larger case head size there will be more action loading due to more Sq/inches of
    surface area.

    The Encore is a strong action but brake open actions can be over loaded and gain more head space
    when loaded with hot loads or loads that they were not designed for.

    Build what you want but be aware of these potential problems.

    J E CUSTOM
     
  6. sambo3006

    sambo3006 Well-Known Member

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    Thanks J E Custom! I did some web research and it backs up what you said about stressing the action. Sounds like I would be better off to go ahead with a 25-06 AI barrel from MGM if I want to scratch the itch. I'm sure I wouldn't have any trouble selling the 257 Wby brass and dies.

    On the rechambering of a standard cartridge chamber to an AI chamber, I have always heard that it is best to set a barrel back slightly (which wouldn't be possible with an Encore barrel without major alteration) so that the standard case will have a slight crush fit in the shoulder to ensure that there won't be any stretching in the case head area during fire forming.
     
  7. IdahoCTD

    IdahoCTD Well-Known Member

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    The head space is slightly different for a AI but it's also a wildcat so you can technically put the shoulder where ever you want it as long as you know that and adjust your dies accordingly. Necking brass up and then back down to create a false shoulder (to make the cases tight in the chamber) or seating a bullet into the lands for fireforming is all that needs to be done.

    One thing to think about also when rechambering is the neck diameter. In the case of your original question, if the neck diameter isn't larger on the Weatherby then you would have a stepped neck because the Weatherby is a longer case and will cut past the original chamber. Rechambering is better when the new cases body will clean up the existing chamber or another words going with a much longer case.
     
  8. Edd

    Edd Well-Known Member

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    You can solve the both headspace and the fire forming issue by building a 257/280AI. There is a member here that did that with a 30 cal Encore barrel. His user name is Buttermilk.
     
  9. J E Custom

    J E Custom Well-Known Member

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    As Idaho CTD said it is a wildcat and you can set the dies up where this does not happen. And by using the 25/06 head space gage with the 25/06 AI reamer it will not change the head space on your 25/06.

    This change will improve the performance of the 25/06, Improve the brass life, and should improve the accuracy. + If you head space it with the 25/06 head space gage you can hunt with 25/06 ammo
    with good accuracy and fire form at the same time. saving one firing to fire form.

    J E CUSTOM
     
  10. sambo3006

    sambo3006 Well-Known Member

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    Interesting and good to know. This is why I posted my question here on LRH in the gunsmithing section because I knew I would get good feedback from people who know what they are talking about. I love learning new things about this stuff. Thanks everyone!
     
  11. Centre Punch

    Centre Punch Well-Known Member

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    sambo, you contender barrel can easily be re-chambered in 257 weatherby, the cartridge is longer and fatter then the 25-06 and will completely remove all traces of the old chamber.
    I must disagree with what has been said about re-chambering to 25-06 AI, the barrel must be sat back to do a proper job, maximum headspace is intended to be .004" shorter then the max headspace of the parent cartridge.
    This is to ensure a crush fit on the parent case shoulder aiding correct fireforming. It is common place to use the parent case Go headspace gauge as a No-Go when gutting an improved chamber together with the correct improved Go headspace gauge.

    Ian.