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MOA formula?'s

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  #1  
Unread 10-08-2011, 12:24 AM
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MOA formula?'s

I am trying to explain this so please bare with me. So I am trying to verify my drop charts, if I impact different than my drop chart says, what is the formula to find out the moa correction at any distance other than 100 yrds.

Darrin
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  •   #2  
    Unread 10-08-2011, 08:17 AM
    Edd Edd is online now
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    Re: MOA formula?'s

    If I correctly understand what you are wanting to do, it would be the measurement in inches on the target divided by the distance in yards multiplied by 100.

    Example: If you were off 2.25 inches at 300 yards.
    2.25 300 x 100 = .75 moa
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      #3  
    Unread 10-08-2011, 10:33 AM
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    Re: MOA formula?'s

    1 MOA is not 1 inch at 100 yards. It is 1.047 inches. That's a 4.7% error.
    In Edd's calculation above the answer is not .75 MOA It should be .716 MOA. Does that matter to your shooting? Only you can decide that.

    Actually the number is not 1.047 but that has less than a 0.02% error. The correct number is irrational and cannot be written as an exact decimal number. Would you use 3 for PI instead of 3.14 or 3.1416 or 3.14159?
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    Unread 10-08-2011, 11:36 AM
    Edd Edd is online now
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    Re: MOA formula?'s

    I knew that was coming as I was typing.

    If being off by slightly less than a half inch at 1000 yards is going to cause a problem, all you have to do is add another step.

    Example:
    You are off 10 inches at 1000 yards.
    10 1.047 1000 x 100 = .955 moa
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      #5  
    Unread 10-08-2011, 01:13 PM
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    Re: MOA formula?'s

    So if I understand this correctly If I am off 6 inches at 400 yrds then

    6/ 1.047/ 400*100= 1.43 moa

    Right after I rounded the decimal\

    Darrin
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      #6  
    Unread 10-08-2011, 01:47 PM
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    Re: MOA formula?'s

    Quote:
    Originally Posted by Edd View Post
    I knew that was coming as I was typing.

    If being off by slightly less than a half inch at 1000 yards is going to cause a problem, all you have to do is add another step.

    Example:
    You are off 10 inches at 1000 yards.
    10 1.047 1000 x 100 = .955 moa
    Your right, that's no big deal if you're doing a second shot correction on a 10 inch miss.
    On the other hand if you're shooting at 1000 yards and cllick up 22 MOA thinking you're getting 220 inches from a 100 yard zero your shot will be about 10 inches high. That may be why "you are off by 10" at 1000 yards" with your first shot. And when hunting how do you see the impact at that distance to know how far you were off?

    If you can see bullet impacts why do any calculations? Just walk your shots onto the target. ;-)

    Last edited by LouBoyd; 10-08-2011 at 02:18 PM.
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      #7  
    Unread 10-08-2011, 01:48 PM
    Edd Edd is online now
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    Re: MOA formula?'s

    Quote:
    Originally Posted by darrindlh View Post
    So if I understand this correctly If I am off 6 inches at 400 yrds then

    6/ 1.047/ 400*100= 1.43 moa

    Right after I rounded the decimal\

    Darrin
    That is correct. There are other ways to way to calculate it but they don't show the trail of how you got the value. Here is a shorter method.

    95.5 x inches yards = moa
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