Can I re cut a 260rem chamber to AI specs without setting my barrel back?

Discussion in 'Gunsmithing' started by ICANHITHIMMAN, Mar 19, 2010.

  1. ICANHITHIMMAN

    ICANHITHIMMAN Well-Known Member

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    Dont know who will have an awnser for this question? I have a 260rem I was thinking of making it a 260AI what is involved in this? Can the chamber just be cut again or doe's the barrel have to be set back?

    Jon
     
  2. tackdriver10

    tackdriver10 Well-Known Member

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    Its my understanding that you should set the barrel back at least one turn. And when it is rechambered to an Ackley, then smith should stop reaming .002 short of the headspace dimension. This way, you end up with a tight jam on the factory case, which makes for a better fireformed case.
     

  3. ICANHITHIMMAN

    ICANHITHIMMAN Well-Known Member

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    Oh the fire forming issue never hit me thats a great point thank you.
     
  4. sambo3006

    sambo3006 Well-Known Member

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    Tackdriver10 is correct. I believe the reason for the AI chamber being a bit shorter resulting in the crush fit on the shoulder is so that the case head doesn't suffer stretching in the initial fire forming.
     
  5. ICANHITHIMMAN

    ICANHITHIMMAN Well-Known Member

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    Gee I didnt think it was shorted if that where the case how would you shoot factory ammo in it?

    Jon
     
  6. loaders_loft

    loaders_loft Well-Known Member

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    the no go gage becomes the go gage or vice a versa.

    anyway, you must set it back to be done properly.
     
  7. tackdriver10

    tackdriver10 Well-Known Member

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    You can still shoot factory ammo. It will just be a tad harder to close the bolt.
     
  8. ICANHITHIMMAN

    ICANHITHIMMAN Well-Known Member

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    Good thoughts guys thanks so much