Wind (again)

Discussion in 'General Airgun Chat' started by Barry, Mar 14, 2019.

  1. Barry

    Barry Member

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    I read somewhere, or someone told me, that wind has its greatest affect on a pellet closest to the barrel it just left.
    This seems counter intuitive if true. I’d have thought the greatest affect would be at farther away ranges as the pellet slows down.

    If it’s true, is there a ballistics expert on here? Who posts really interesting and fascinating information, who could maybe explain this to me please?
     
  2. Conor

    Conor Never been banned from sales Staff Member

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    There’s loads of ballistic experts on every shooting forum however the only shot they have ever fired is their own ‘load’.
     
  3. Barry

    Barry Member

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    My post is ‘aimed’ (see what I did there?) at one in particular Conor. Ballisticboy........
    :)
     
  4. RobF

    RobF Administrator Staff Member

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    It does, but not in the way that you think.

    If wind blows and then stops then the pellet keeps travelling in that new direction rather than turning back onto it's original path. So the further away from the target this happens the greater the effect.
     
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  5. Barry

    Barry Member

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    Thanks Rob. That makes absolute sense and maybe the intended message behind what I read, even if it didn’t specify that.
    Cheers
     
  6. Ballisticboy

    Ballisticboy Active Member

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    Its simply as Rob says, the further away from the target the pellet changes its flight line then the bigger the effect will be. The diagram below shows the effect of a cross wind in the first 10 yards or the last 10 yards of a 50 yard trajectory.

    cwind3.jpg
     
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  7. Darron

    Darron Dwarf Slayer

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    I will give it half a kill
     
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  8. Barry

    Barry Member

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    Got it.
    So a brief puff of wind as the pellet leaves the barrel at the gun position, will set the pellet on a different course, which results in a bigger miss the further out the target is. Whereas the same brief puff of wind at the target end of the distance won’t affect the flight line so much because the distance left to travel is a lot less.
    I kinda knew that. I think it’s what I read into the original statement that threw me. I was over simplifying.
    Thanks for the information.
     
  9. dave croucher

    dave croucher FT, the sport where simple becomes complicated

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    Who knew???
     
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  10. Darron

    Darron Dwarf Slayer

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    that's how I believe it to be
     
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  11. C.Eaton

    C.Eaton Confirmed Anschutz Nut...

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    I always take it that the first 10% of flight has the biggest effect unless there is a hooley blowing at the target end...
     
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  12. nat

    nat Member

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    o_O
     
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  13. hmangphilly

    hmangphilly Floppy Quick Phil

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    It's all the wobbling about just before the trigger is pulled that mucks it up for me
     
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  14. C.Eaton

    C.Eaton Confirmed Anschutz Nut...

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    ah yes, but 50% of the time you'll wobble and give correct windage....;)
     
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  15. DeanB

    DeanB Active Member

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    My question has no practical relevance but I am interested. Why does the predicted deflection reduce between 6 and 10 yards from the muzzle, and why is the relationship between predicted deflection and distance not a smooth one?
     
  16. hmangphilly

    hmangphilly Floppy Quick Phil

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    I feel a lot better for that .
    Thanks Colin
     
  17. C.Eaton

    C.Eaton Confirmed Anschutz Nut...

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    No problem mate, silver lining and all that...;)

    What I find as interesting is seeing the yawing of the pellet, you can see it in the long track...:D
     
  18. Ballisticboy

    Ballisticboy Active Member

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    As said above it is just the pellet swerving around as the yaw on it from when it first enters the cross wind causes it to heave and swerve as they say. Some people call it epicyclic yaw, it largely cancels itself out as it moves down the trajectory if you have a well behaved pellet but it does show how if you have your target at the wrong distance you may get an error but it will be extremely small.
     
  19. C.Eaton

    C.Eaton Confirmed Anschutz Nut...

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    This is quite illustrating, albeit for a bullet, notice the way the yawing is circular and calms down after the first 100yds.
    Pellets must be similar.
     
  20. DeanB

    DeanB Active Member

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    Two points I would make. 1. As you have said, the effect is extremely small. 2. We don't produce a click chart based on one shot at each distance. Slight variations from one pellet to another, and small changes in the wind from shot to shot, would hide the effects of yawing when we take an average from say 10 shots.
     

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