Measurement of crimp in 45ACP

Discussion in 'Reloading' started by XDRoX, Mar 29, 2010.

  1. XDRoX

    XDRoX

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    I'm not as comfortable loading 45 as I am with 9mm yet.
    With 9mm I try to make the crimp measurement .377" - .378", which has been working great.
    But if I'm not mistaken isn't a 45 the same width all the way up, where as a 9mm case actually cones in slightly???

    If this is true then should I just make sure that the top of my 45 case is the same size as the bottom? In other words I should just be taking out the bell right?

    Thanks
     
    Last edited: Mar 29, 2010
  2. GioaJack

    GioaJack Conifer Jack

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    Don't lose sleep over the amount you crimp your .45's, or the 9's for that matter... it's not nearly as critical as some would think.

    At the bare minimum you need to take out the flare or the round will not chamber... smooth that out and if you end up crimping it a bit too tight it won't hurt a thing. (You don't want to crimp so tight that the brass starts to fold over on itself on a jacketed bullet or break through the coating of a plated bullet. Lead bullets are much more forgiving.

    Eliminate the bell, drop a couple rounds in your barrel and made sure the base of the case is sitting flush with the barrel hood. Not enough crimp and the base will sit above the hood, gun will fail to go into battery or be susceptible to a slam fire... too much crimp, (way too much crimp) and the round will fail to headspace properly on the case mouth leading to a failure to fire... firing pin, or striker will not be long enough to reach primer with full contact.

    Many newbs don't realize that lots and lots of loaders went years without ever owning a set of calipers... they weren't that common and tended to be expensive. We just compared the OAL to a factory round, or a buddy's reload and shot 'em.

    Not as scary as it sounds... there weren't nearly as many powders to choose from back then nor as many bullet configurations... lots of history with the components that were available at the time.

    Crimp 'em, make sure they function and go have fun,

    Jack
     

  3. fredj338

    fredj338

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    Jack is so right. I loaded w/o calipers for about 8yrs! Crimping the 45acp is actually easier because the case is straight. If you can't see the bell & the round fits in the chamber or case gage, that is all the crimp you need.
     
  4. kimberguy2004

    kimberguy2004

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    If you want to measure .45ACP crimp, .468-.470 will work.
     
  5. JesseCJC

    JesseCJC

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    .468 seems like a really heavy crimp. Mine is set to .471 and factory is usually around .473
     
  6. kimberguy2004

    kimberguy2004

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    It may be, but that's what I read in Bill Wilson's maintainance manual. I tried it and it works, so I never saw a need to tinker with it..