LoadBase 3.0 question

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Mike6158, Dec 21, 2009.

  1. Mike6158

    Mike6158 Well-Known Member

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    I'm trying to figure out where to come up with a gyroscopic stability factor for a particular bullet so I can use the Spin Drift part of LoadBase 3.0. The default value is 1.5.

    The example in the Appendix (Equation 6.1) of Applied Ballistics for Long Range Shooting uses a gyroscopic stability factor of 1.5 but doesn't say why.
     
  2. phorwath

    phorwath Well-Known Member

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    There's a tab in the Analyzer Module that allows for the determination of the stability factor. It's called Twist & Stability in LB3D. Requires that you input bullet length, actual twist rate, bullet diameter, bullet weight, and MV. Click the Standard Conditions is "ON", and input the value that's highlighted in yellow background in the Ballistics Module. That's about it.

    There will be detailed instructions on how to calculate the appropriate stability factor in the LB3 Users Manual provided with your LB3 ballistics program package.
     
    Last edited: Dec 22, 2009

  3. Mike6158

    Mike6158 Well-Known Member

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    Cool. Thanks. I did a search in the help tab in the program and it didn't come up with anything.

    I appreciate the help

    Merry Christmas to you and yours
     
  4. Mike6158

    Mike6158 Well-Known Member

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    The latest version has a bug in the Twist and Stability module. I sent them an email. When I try to print to paper or PDF it wipes out the atmospheric data and prints a different result than what is on the screen.
     
  5. jmason

    jmason Well-Known Member

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    I'll bet Gus fixes you up in short order!:)