Dialing For Distance

Discussion in 'Long Range Scopes and Other Optics' started by Muttt, Mar 22, 2012.

  1. Muttt

    Muttt Well-Known Member

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    Jan 28, 2012
    Ok,

    In the past I've always used cheap scope for hunting and shooting. I'd zero them for point blank range and then just use hold overs. This has worked out well out to 300 yards or so.

    Recently I bought a Viper Vortex. It has 1/4 MOA adjustments. I've never really dailed for distance before and I am a little confused. Since my scope is 1/4 MOA, I assumed that it was 1/4 inch at 100, 1/2 inch at 200, 1 inch at 400 etc .....

    But, when I run my velocities for my ammo through JBM, it gives me way different numbers.

    For drop in inches at 100, 200, 300 and 400 it says .....

    0.0

    4.3

    15.8

    35.9

    For drop in MOA it says .......

    0.0

    2.1

    5.0

    8.6


    Shouldn't these two sets of numbers be the same??

    I hope someone can clear this up for me.
     
  2. JackinSD

    JackinSD Well-Known Member

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  3. sp6x6

    sp6x6 Well-Known Member

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    it gave you the drop in inches and the moa correction. 1moa=4[1/4] on your scope4.3''= 2.1x2,for 200yrd.35.9'' =8.6x4 for 400 yrd drop.that should be more like 8.9
     
  4. Greyfox

    Greyfox Well-Known Member

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    Jan 21, 2008
    The numbers your calculator gave you are correct. One MOA is not equal to one inch, it is equal to 1.047". For example, your 300 yard value:

    15.8"/3= 5.27, 5.27"/1.047=5MOA. This is correct.
     
  5. sp6x6

    sp6x6 Well-Known Member

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    Can tell Ive been shooting mil for a while:D
     
  6. Scot E

    Scot E Well-Known Member

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    1 MOA is 1.047 of an inch so each click of a true MOA scope should be .26 of an inch. But your scope may or may not perform to those specs. Be sure to check your turrets to see how they perform. This isn't necessary for close range work but will be as you start to push the distance.

    Your general statement about MOA clicks growing at distance is correct. But the ballistic calculator is telling you how many MOA you need to adjust, not how many clicks. 4 clicks = 1 MOA.

    Do a search from the Google search button at the top of this page. There are a lot of good threads going into detail about this.

    HTH,

    Scot E.
     
  7. Muttt

    Muttt Well-Known Member

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    I get it. I don't know what the hell I have been thinking. No wonder I got lost in my scope when I was at the range. Had to go back to zero at 100 yards and then work it out again to get on at 545 yards. I was thinking each click was 1/4 inch and so one. Not so. I did manage to take the info and make a drop chart for my rifle using clicks. I just multiplied the MOA measurements by four and went with that.
     
  8. JackinSD

    JackinSD Well-Known Member

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    Glad you got it. I didn't figure it would take you much. Brain farts, I hate them.
     
  9. Scot E

    Scot E Well-Known Member

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    Glad you got it! I would encourage you though to begin to think in MOA and not clicks as soon as possible. It is a much easier way to think and you are dealing with much smaller numbers so less mistakes are made. Also knowing how many MOA per rev of the turret is a much quicker way to dial in since the MOA markings are always on the turret but the number of clicks aren't.

    Scot E.