Best range to test bullet stability

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Iclimb, Sep 10, 2013.

  1. Iclimb

    Iclimb Well-Known Member

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    I want to run some 180 berger bullets through my 7mag long-range hunter, to check for stability and I was wondering at what range minimum do I need to get out to check it? I checked it on a stability calculator and my altitude 4500 to 8000 feet it shows it as being moderately stable anyone else shooting them an LRH 9 1/4 twist?
     
  2. MontanaRifleman

    MontanaRifleman Well-Known Member

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    When I use the twist calculator, I check for worse case altitude and temp. The lower the altitude and/or temp, the less stable the bullet. A stability factor of 1.1 or better should be stable enough for flight through the air and paper punching. A stability factor of 1.5 is more ideal and recommended for terminal performance stability inside 500 yds.. So it's possible to have a bullet that appears stable when target shooting that might have terminal performance issues inside about 500 yds. The farther down range you get, the more stable the bullet becomes. If your bullets are making nice round holes @ 500 yds, they should be stabilizing OK.
     

  3. Iclimb

    Iclimb Well-Known Member

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    Looking to get 800 to 900 yds. I'll run the calculations again I can't remember what it was coming up with. I would have thought it would get less stable the farther I got.... Learn something everyday.
     
  4. MontanaRifleman

    MontanaRifleman Well-Known Member

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    The bullet gets more stable because the rate of spin does not decrease as fast as velocity decreases going down range.