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Need help with "true velocity" for a drop chart

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  #8  
Unread 07-31-2011, 02:52 PM
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Join Date: May 2011
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Re: Need help with "true velocity" for a drop chart

I hadn't checked the scope movement but I just did that and it is right on (moved 25 inches with 25 MOA movement on the scope at 100 yards).
The terrain is flat (some hills around but actually shooting level). No wind to push the bullet up or down.
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  •   #9  
    Unread 07-31-2011, 02:58 PM
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    Re: Need help with "true velocity" for a drop chart

    If you check your optic for like 20 MOA and it moves right on at 20 inches at 100 then your moving in IPHY not MOA which will catch you once you get out there and you will shoot low, just a possibility that has to be covered.
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      #10  
    Unread 07-31-2011, 03:19 PM
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    Re: Need help with "true velocity" for a drop chart

    correct. I just learned that little piece of information. It should have moved 26.175" not 25". I reran the numbers but I still have a calculated velocity difference of about 200 fps. The close range gives me 2872, the far range gives me 2695.
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      #11  
    Unread 07-31-2011, 03:33 PM
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    Re: Need help with "true velocity" for a drop chart

    What scope? Sounds like a tracking issue to me.

    Jeff
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      #12  
    Unread 07-31-2011, 03:37 PM
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    Re: Need help with "true velocity" for a drop chart

    Ok,

    200 yard zero,

    180 Berger

    Conditions Wind none, temp 65, pressure 25.20, elevation 4950.


    Scope height above bore?

    Give us your actual needed dial ups you have confirmed and their exact distances. I assume you shot at least 3 shots to comfirm each?

    Jeff
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    Last edited by Broz; 07-31-2011 at 03:41 PM.
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      #13  
    Unread 07-31-2011, 06:26 PM
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    Re: Need help with "true velocity" for a drop chart

    scope height 1.75" (leupold VX 3, 4.5-14)

    zero 200 yards
    465 yards, 27 clicks (6.75 MOA) 5 shot group, 5.1 " high
    753 yards, 64 clicks (16 MOA) 5 shot group 2.8" low
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      #14  
    Unread 07-31-2011, 07:01 PM
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    Re: Need help with "true velocity" for a drop chart

    Quote:
    Originally Posted by kudu View Post
    scope height 1.75" (leupold VX 3, 4.5-14)

    zero 200 yards
    465 yards, 27 clicks (6.75 MOA) 5 shot group, 5.1 " high
    753 yards, 64 clicks (16 MOA) 5 shot group 2.8" low
    No rail base? The scope height numer looks low.

    I will run some numbers and report back.

    Jeff
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