Finished Length

Discussion in 'Gunsmithing' started by Crane, Mar 25, 2009.

  1. Crane

    Crane Well-Known Member

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    Why would you loose any length in a contured blank? I know it has to be threaded and crowned but that shouldn't shorten it.
     
  2. winmagman

    winmagman Well-Known Member

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    Mar 13, 2003
    Crane,

    As I understand things when a barrel is lapped it gets "belled out" on both ends when the lead swage comes in and out of the barrel. Thats not really a big deal on the chamber end becuase it gets opened up past that point when its chambered, on the crown end it's bad juju. So they usually cut at least 1" off that end.

    Plus you lose a little when the ends are squared up for chambering or crowning, but that amount is usually minimal.

    Chris
     

  3. J E Custom

    J E Custom Well-Known Member

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    Jul 29, 2004
    You "must'' clean both ends of a new barrel to check it between centers before starting
    any work because you want it true to the bore and a fresh cut will help.

    Some barrel makers actually make a saw cut on the muzzel end to force you to remove
    the end back to good barrel and also on straight barrels (No taper) to indicate the muzzel
    end (The bore is tighter at the muzzel buy the spec. required )

    Normaly it is only .0001 or .0002 but it makes a differance in how accurate the rifle will
    be if placed in backwards.

    Most of the time the smith can save all but about 3/4 of an inch of the barrel length.( a
    28" blank will clean up at about 27 3/8'' max.

    So if you want a 30'' finished length you would get a 31''+ blank.

    A barrels finished length is normally listed by the barrel maker.

    J E CUSTOM
     
  4. Crane

    Crane Well-Known Member

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    Thanks for educating me, now I hope it comes in conversation some day so I can sound like I know what I'm talking about!