How much does humidity really affect ballistics?

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Alan Griffith, Jun 20, 2007.

  1. Alan Griffith

    Alan Griffith Well-Known Member

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    I have a Kestrel 2500. Really enjoy it. Am wondering if going to a Kestrel 3000 w/ humidity function will really make a difference in 600 yd to 1500 yd shots?

    I hunt in the west from 4500' to 11000' with a 30 cal, .507 bc, doing 3000-3050 fps.
     
  2. goodgrouper

    goodgrouper Well-Known Member

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    Just about zilch. Benchrest shooters who load at the range watch it because it can change the thrown weight of volume type powder throwers and push you out of "tune" but it hardly makes any difference on exterior ballistics.
     

  3. royinidaho

    royinidaho Writers Guild

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    What if?

    I would suppose zilch means I don't need to worry about %Hum when shooting a big game @ LR.

    What about chuck's and the small stuff?
     
  4. edge

    edge Well-Known Member

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    Not an expert by any means, but I think that drop will increase by less than 2 inches. Assuming sight in @ 70% and actual conditions are 10% humidity @ 1000 yards. Seems like the least of your worries.....unless that last 2 inches make or break the shot location.

    edge.
     
  5. Shawn Carlock

    Shawn Carlock Sponsor

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    It is tough to put a value on humidity only. If you go into a program and only change the humidity it will make almost no difference, however it is a lesser but key component of barometric pressure and BP will have a fair amount of affect on flight. Like with all conditions it depends on distance as to how important any of it is.
     
  6. Alan Griffith

    Alan Griffith Well-Known Member

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    Well, if obvious none of you have any stock shares in Kestrel! /ubbthreads/images/graemlins/laugh.gif

    Guess I'll keep my 2500.
     
  7. ss7mm

    ss7mm Writers Guild

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    It's one of those things that is similar to some steps we go through in the case prep and reloading process. When I turn my Kestrel and Palm on it only takes me a few seconds to enter the humidity so I do it. I agree that for all practical purposes it's a non-issue but my feeble little brain likes to control everything I can, and a few seconds spent keeps my subconscious happy, and that keeps my anal side happy. /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/smile.gif /ubbthreads/images/graemlins/grin.gif

    If your meter doesn't have it, don't sweat it. At most ranges and under most conditions you can forget it. If you like controlling everything you can to eliminate all variables for that looooong range shot........then use it. /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif
     
  8. royinidaho

    royinidaho Writers Guild

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    [ QUOTE ]
    It's one of those things that is similar to some steps we go through in the case prep and reloading process. When I turn my Kestrel and Palm on it only takes me a few seconds to enter the humidity so I do it. I agree that for all practical purposes it's a non-issue but my feeble little brain likes to control everything I can, and a few seconds spent keeps my subconscious happy, and that keeps my anal side happy. /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/smile.gif /ubbthreads/images/graemlins/grin.gif


    [/ QUOTE ]

    Me too /ubbthreads/images/graemlins/crazy.gif
     
  9. Mikecr

    Mikecr Well-Known Member

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  10. eshell

    eshell Well-Known Member

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    [ QUOTE ]
    Well, if obvious none of you have any stock shares in Kestrel! /ubbthreads/images/graemlins/laugh.gif

    Guess I'll keep my 2500.

    [/ QUOTE ]
    LOL, I love my Kestrel 4000, and use the "Density Altitude" function to replace worrying asbout RH, Temp and absolute Altitude.
     
  11. Mikecr

    Mikecr Well-Known Member

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    How do you do that Ed?
     
  12. Guest

    Guest Guest

    Humidity effects the flight of the bullet 1/10th of 1%; or roughly 1/100th of an inch at 1000 yards.
    However, if the shooter is in a Hot and Humid environment, (100° F + 100% humidity) the velocity of the bullet will increase. This is due to the fact that water molecules are lighter than air molecules.