Ballistics Programs (Web based & Downloadable)

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Dave King, Dec 24, 2004.

  1. Broz

    Broz Well-Known Member

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    I am not sure if any "free on line" calculators do. But I know with Both Applied Ballistics and Shooter you can add multiple BC's and velocity limits as you want. But for most general long range use to 1000 yards 1 is usually sufficient.

    Jeff
     
  2. Ring

    Ring Well-Known Member

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    if you use the G7, this is irrelevant... the G7 doesn't change based on FPS like a G1
     
  3. MSU Marksman

    MSU Marksman Well-Known Member

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    For the Sierra 155 Palma bullet they list a BC of .504 above 2700 fps, and .470 below. If fired at 2900 fps at the muzzle, the bullet hits that magic 2700 fps mark around 100 yards. That means the majority of its flight would be at the lower BC.

    I checked my early version of the Applied Ballistics calculator and it doesn’t have the option for the multiple BC’s.

    I’d use the G7 if I had it, but I haven’t found it for this bullet yet. (Admittedly I haven’t checked my Applied Ballistics book either.)
     
  4. Ring

    Ring Well-Known Member

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    0.308 Sierra Palma (2155) 155 G7=0.214
    0.308 Sierra Palma (2156) 155 G7=0.229
     
  5. Broz

    Broz Well-Known Member

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    I am not sure this is completely accurate. You may want to research this. Although it may be true that the changes are less with G7 compared to G1 they still change. I have received G7 Ballistic data from well know Ballistic experts that do indeed show G7 BC changes with velocity at many many different sample velocities. This the reason ballistic apps offer velocity limits and multipul BC's in the program for BOTH G1 and G7. Applied Ballistics even offers another choice other than G1 or G7 that is "Custom Drags" This is what I use now and have found it to be very accurate even at 3000 yards.

    Never the less I was simply answering the question MSU Marksman asked. And I believe my answer to be correct.

    Jeff
     
  6. Ring

    Ring Well-Known Member

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  7. Broz

    Broz Well-Known Member

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    I agree, that G7 is a better choice with less change as I indicated in a prior post. Using a wider set of velocity samples from zero to 3500 fps with the same bullet can reveal a G7 BC of a high BC bullet to change of as much as .148. However using the average will get you very close, especially at shorter distances where the velocity spread is less. So I agree a single G7 may well be the best choice. At least for most and all practical purposes. But I have had Bryan Lintz help me in the past as I worked out a set of stepped G7 BC's for a 338 Lapua to 2500 yards from actual recorded field drops that were repeated and believed to be correct. He confirmed my finding to be accurate in his opinion after we tested and eliminated other factors like scope tracking and muzzle velocity. That said he also helped me to average and find a single BC that was very close in relation to what I had recorded for data.

    So I am not debating that a single G7 is not the best choice for most all shooters. But what I am saying is true that, once again " G7 does not show as significant of a change as G1" but it does indeed show change with velocity.

    Jeff
     
  8. Broz

    Broz Well-Known Member

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    I will also add for what it's worth. It may surprise some to know even a G7 BC is not lineal to slowing velocity. As velocity drops you can actually see BC drop , then increase then drop again or visa versa.

    Jeff
     
  9. amce

    amce Well-Known Member

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    A question about Shooter (hope I'm not over-thinking here): when inputing the range to target when shooting at an angle should one use the horizontal distance or actual distance?


    Cheers
     
  10. Ring

    Ring Well-Known Member

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    if you're using shooter to do the angle measuring, it will do it all, but unless you're shooting over 15^, don't worry about it, it wont have any effect..
     
  11. amce

    amce Well-Known Member

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    Thanks for the reply. Yes, I realise this but I would still like to know if the input value is true distance or horizontal distance. If shooting at angle of, say 20°, which one do I use?


    Cheers
     
  12. Ring

    Ring Well-Known Member

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    put in the true lazed distance, set shooter to 20°, it will tell you the horizontal "ballistic" distance
     
  13. amce

    amce Well-Known Member

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    Thanks, mate

    Cheers
     
  14. DocUSMCRetired

    DocUSMCRetired SPONSOR

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    Our web based ballistic calculator has now been updated with the new 400 bullet library. It now has all the custom curves currently available from our ballistics laboratory! It also includes a Light version of WEZ (Hit probability), and it includes the ability to export the profile, and upload it to a Kestrel 4500 AB model with the profile loader.

    Ballistics Calculator | Applied Ballistics, LLC