.243 case dimensions

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Aussie, Sep 22, 2004.

  1. Aussie

    Aussie Well-Known Member

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    Apr 29, 2004
    Anyone had experience with Winchester .243 brass being significantly undersize when measured at the case head ? According to my source the measurement should be .471 .
    My brass measures .463 before first firing . Expansion ring measures .475 after firing so quite an unsightly bulge .Is this a problem or just cosmetic ?
    Thought my gunsmith must have used an oversize reamer at first .Any comments ? It's a .243 Ackley by the way .

    [ 09-22-2004: Message edited by: Aussie ]
     
  2. brian b

    brian b Well-Known Member

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    Aug 15, 2004
    Aussie,
    I know exactly what you are talking about,
    Win.brass is often undersized. you will
    never find the .471 you are looking for but
    the Lapua 243 brass is .469 instead of Win.
    being .463
    I discussed this same thing under "what is
    best brass for 22-250AI" check it out you
    will be amused (or horrified)
    B
     

  3. Aussie

    Aussie Well-Known Member

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    Apr 29, 2004
    Brian ,
    Thanks for the info.
    It was your comment on .22/250 brass that prompted this thread .
    Would still be interested in any comments on my chamber dimensions if any gunsmiths read this .
     
  4. LB

    LB Well-Known Member

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    Jul 22, 2004
    This phenomenon has existed for a very long time, for whatever reason? It may be shrinkage in the molding/casting process? It may also be intentional, as with autoloaders? Think AR forward assist. I think you can order small base dies, for some cartridges; for sure 223 Remington? But, it never has created "much" of a problem, other than esthetics....so far as I know? And, it's true, I don't know that much. [​IMG]

    Good hunting. LB
     
  5. goodgrouper

    goodgrouper Well-Known Member

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    Sep 3, 2004
    LB,
    Great point. I never really thought about the dies/moldings shrinking over time but It sounds perfectly conceivable. I'll bet if that's the case, they probably know about it but won't ever change it due to cost of new dies, but they should!