Best way to measure OAL?

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by cbaker, Jul 14, 2004.

  1. cbaker

    cbaker Well-Known Member

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    I consistently measure the OAL by closing the bolt and marking on a cleaning rod the distance to the bolt, then putting a bullet in where it touches the lands and then making another mark on the cleaning rod. Is there a better, more accurate way? Thanks.
     
  2. Varmint Hunter

    Varmint Hunter Well-Known Member

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    Why don't you just use a caliper and measure the cartridge (case base to bullet nose)directly?

    I might add that it is important to assure that primers are properly seated below the case head. If they protrude slightly you will get erroneous measurements.

    Are you measuring COL to match info provided in a loading manual?

    VH
     

  3. cbaker

    cbaker Well-Known Member

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    What I am really try to determine is how do I determine how long the cartridge should be, to be just off the lands?
     
  4. shilen30

    shilen30 Well-Known Member

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    Here is one post from here that was brought up a few days ago. You will find this very enlightening. I would certainly start your loads just off the lands (say .005"), work up a good load with that OAL, and then when you find the proper bullet/powder/charge combination, then vary OAL (.005" at a time)till you get best accuracy. And do yourself a HUGE favor and save yourself a lot of headaches: buy a stoney point bullet comparator or the comparator at sinclair international.
    http://www.longrangehunting.com/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=3&t=002175

    P.S. Read through the whole post before making up your mind on how you will do it for sure, then ask more questions later.

    [ 07-14-2004: Message edited by: shilen30 ]
     
  5. Varmint Hunter

    Varmint Hunter Well-Known Member

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    Shilen is on the money advising you to purchase a Stoney Point OAL gauge or similar device.

    Measuring actual OAL from case base to bullet point will do little to help you gauge the distance from bullet ojive to land engagement. Some bullets have a wrinkle like hollowpoint that varies in length considerably.

    The Stoney Point is inexpensive and works great.

    VH
     
  6. shilen30

    shilen30 Well-Known Member

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