bullet drop vs up or down hill shooting

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by kidcoltoutlaw, Jul 8, 2002.

  1. kidcoltoutlaw

    kidcoltoutlaw Well-Known Member

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    exbal is the program i for my shooting.i can change it to show that im shooting up hill at 35 or 45 degrees it will change the bullet drop.it will drop less but it does not change the clicks that are used to put you on target.the clicks change the bullet impact.how can the drop be less but the number of clicks stay the same ????????,thanks,keith
     
  2. Guest

    Guest Guest

    kid,
    Can't be right. Less drop, less clicks. Try another program. [​IMG]
     
  3. Dave King

    Dave King Well-Known Member

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    338-378 is correct.

    There are a few things I feel should be addressed in the interest of dragging this out (can't help it guy it's in my nature).

    Even though the drop is effectively less on angled shots the wind component remain the same for angled or horizontal shots (assuming the same wind conditions). The wind deflection is a factor of Time Of Flight (TOF) and not gravity. TOF remains the same (essentially) whether the shot is on an angle or the horizontal for similar Line-Of-Sight distance(s).
     
  4. kidcoltoutlaw

    kidcoltoutlaw Well-Known Member

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    if you run 1000 yards on your program at zero degree's then run it again at 35 degree's will the number of clicks stay the same.
     
  5. Dave King

    Dave King Well-Known Member

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    Yes AND No, the numbers will change for the elevation "clicks" but remain the same for the windage "clicks"

    The elevation "clicks" will change (basically this is correct but not exact) by a factor equal to the cosine of the angle.

    The cosine of 35% is .819 so the number of clicks should equal that required for a 819 yard shot, not a 1000 yard shot (this is the method most often used and is accurate enough). Remember that the projectile is still traveling 1000 yards through the air so the windage will still be that required for a 1000 yards shot.
     
  6. kidcoltoutlaw

    kidcoltoutlaw Well-Known Member

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    with my program it shows a change in the number of inches of drop but not in the moa for correction.sounds like there is a problem with the program.i can still use it .just go buy the inches of drop because it changees.is that right,thanks,keith
     
  7. Dave King

    Dave King Well-Known Member

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    Sure, you can still use it. I'd just figure the "gravity" distance and plug that in as the distance then use the computed MOA drop for that new "gravity" distance.

    If you're using Exbal, you must have a computer. I'd assume you have Microsoft Windows. In Windows you have a calculator. Start the calculator, select VIEW from the manu bar and change to Scientific. Make sure the Scientific option includes a checked Degrees radio button. Enter the angle you desire and press COS. The result is the factor you multiply the Line-Of-Sight distance by, the new answer is the "gravity" distance. Enter the final answer into Exbal and you have the (perhaps if everything else is working) correct answer for the angled distance.

    You can make a handy little chart of Cosines if you like and carry it with you.