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Is my calculation correct?

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Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: December/09/2016 at 12:16
tpcollins View Drop Down
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I understand the Sniper's formula "target height inches divided by MOA x 100 = distance in yards".

The upper section of the Zeiss RZ-800 reticle can be used for a ranging an 18" tall target but must be used at 15x on their 3-15 HD5 scope. And at 15x, an 18" tall target (deer belly to top of back) fills (3) of the spacings, which are 2" each for a total of 6".

So Zeiss takes 18" / 6" = 3 x100 = 300 yards to the target if it fills those (3) 2" spaces.  

But I would like to be able to range that target at 10x instead. So would I take 15x divided by 10x = 1.5 x 6" = 9", so 18" / 9" = 2 x100 = 200 yards to the target if the 18" fills the same (3) 2" spacings? Thanks.


Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: December/09/2016 at 14:25
Rancid Coolaid View Drop Down
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Target size (in) x 95.5 divided by size in MOA = distance (yards)

I think.
I am still struggling with why someone is still using MOA.

Opinions vary.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: December/09/2016 at 14:33
tpcollins View Drop Down
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Originally posted by Rancid Coolaid Rancid Coolaid wrote:

Target size (in) x 95.5 divided by size in MOA = distance (yards)

I think.
I am still struggling with why someone is still using MOA.

Opinions vary.

That's not exactly what I'm asking.  My question was whether I was converting the 18" tall image fill correctly with the magnification turned down to 10x instead of the specified 15x? 



At the top of this RZ reticle are the lines that represent 2" each when the magnification is set at 15X. If the deer's body fills 3 of them that's 6".  18" / 6" = 3 x 100 = equals the 300 yards away the target is - per Zeiss.  I want to know if it fills those 3 spaces at 10x is the target 200 yards away?



Edited by tpcollins - December/09/2016 at 14:47
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: December/09/2016 at 16:34
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Yes, it would be 200 yds away.

Originally posted by tpcollins tpcollins wrote:


I want to know if it fills those 3 spaces at 10x is the target 200 yards away?

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: December/10/2016 at 10:22
Rancid Coolaid View Drop Down
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One note: companies do not usually calibrate the mid-mag range, just the ends. It is entirely possible the 10X marking is not exactly 10X, but that can be calculated with a grid, and some simple math.

And sorry, I didn't read all of the first post, I sometimes test poorly due to knowing the answer before I hear the whole question.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: December/10/2016 at 12:43
tpcollins View Drop Down
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I understand how to do that Rancid, if I get that scope I'll verify it both at 5x and 10x.  Thanks.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: December/25/2016 at 20:48
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That reticle does have the capability of about .1 of .5 inch per hundred yds. interpolative accuracy for rangefinding if using the .5 IPHY markings as your std. subtension in the formula instead of 2. Always wanted to play around with the Zeiss reticles for rangefinding using those tiny subtensions.
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