case rim clearance to bolt face

Discussion in 'Gunsmithing' started by skik, Jul 28, 2015.

  1. skik

    skik Member

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    Jul 24, 2015
    Hi all
    i am currently in the research stages of a project build it will be a left hand action 303epps
    on a 308 bore i have chosen 308 simply for the greater projectile selection i am looking for a donor rifle my main question is if the case rim on a 303 is .540 is using a action chambered for a case head diameter of .545 going to be to much clearance
    any help will be greatly appreciated thanks
     
  2. J E Custom

    J E Custom Well-Known Member

    Messages:
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    Jul 29, 2004
    If both of those dimensions are correct. It will be fine.

    A bolt face needs to be slightly larger than the case rim so it will eject. anywhere from .005 to .007
    larger than the rim is good.

    J E CUSTOM
     
  3. skik

    skik Member

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    Jul 24, 2015
    thanks J E CUSTOM
    my original post i quoted rim diamiter .540 for the 303british rim i was going off my hornaby reloading manual i have measured a few mill surplus and a few pmc cases and they all seem to be close to .527 so would the easiest way to see if it will work be to chase up something chambered with a case head of say .525-.532 and see if the 303 head will work in the bolt face whatever donor rifle i choose will be rebarreld anyway but i figure if i can find something that doesn't need bolt work its one less expense for my project