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#65882 - 03/06/10 09:02 PM

Re: Drop compensation?? [Re: Ernie]

TCTex.
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On which power setting?

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#65885 - 03/06/10 09:15 PM

Re: Drop compensation?? [Re: TCTex.]

Dan B.
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I'd say the highest to minimize the room for error from the center to edge.

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#65904 - 03/06/10 10:24 PM

Re: Drop compensation?? [Re: Dan B.]

sscoyote
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Tigger- just looked again at that Clearidge optic and they use a .25 mil for their dots. That's an odd size these days--most have gone to the 0.2 mil dots--interesting. Are they oblong or circular?

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#65950 - 03/07/10 02:27 PM

Re: Drop compensation?? [Re: sscoyote]

Tigger
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The dots are round. I just looked at the chart and I don't see what you mean by .25 Mil dot? I see the dot size listed as 2.18 on 6X, .9 on 14X and .62 on 20X.

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#65976 - 03/07/10 07:44 PM

Re: Drop compensation?? [Re: Tigger]

sscoyote
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Here are the pics that explain it the best--

Yours is the bottom system (though it's circular instead of oblong). It's designed to break the mil-dot down into 1/8th (0.125) of the 3.6 IPHY subtension between dots, since 0.9 IPHY = 3.6 IPHY x .25

the top system is designed to break it down (interpolate) to the tenth (0.1)--0.72 IPHY = 3.6 IPHY x .20

just like the pics show.

The nice thing about the systems is no matter what power you are on, the relative relationship between the dots and the dot to dot measurements remain the same. If your subtension is 3.6 IPHY between dots or 2.48 the dots will still be .2 or .25 "mil" of that subtension.

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#65987 - 03/07/10 10:15 PM

Re: Drop compensation?? [Re: sscoyote]

TCTex.
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I went out this evening... a armadillo is 1.5 mils at 100 yards...

I ranged three of them with a rangefinder and then came up with a mill reading. Next weekend I think I will be going to the 500 yard field and seeing what I can't range, and then laser!

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#66007 - 03/08/10 01:43 AM

Re: Drop compensation?? [Re: TCTex.]

sscoyote
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Sounds like fun Duane. I bet armadillos would be fun to do that on.

One of the main advantages of the mil-ranging formula is that it lets u know what kind of accuracy u can expect from the system. For the coyote above if i were just +/- 0.1 off in the interpolation , then here's the error--

1100/3.14/.5=700
1100/3.14/.7=500

that's 200 yds. of error for +/- .1 unit. THAT"S TOO MUCH (which is the reason that my system only goes to 480). 3 MOA is too big for rangefinding beyond ~400-480 or so. For rangefinding further than that i need a smaller subtension or larger tgt.

Interpolating for downrange zeroing leaves some room for a little error--way more so than for rangefinding. Things get geometrically more difficult the further out u go.

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#66013 - 03/08/10 07:34 AM

Re: Drop compensation?? [Re: sscoyote]

TCTex.
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LOL... That is the same reason I am Mil'ing it threw the scope, ranging finding it with a laser, and then seeing what it looks like threw the 2-7 Burris handgun scope... and then shooting it!!! So far I am 3 for 3 at 100 yards and 1 for 1 at 200.

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#66021 - 03/08/10 09:25 AM

Re: Drop compensation?? [Re: sscoyote]

Tigger
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OK Steve, I see exactly what you mean. I went and looked at the syatem again and was able to extrapolate the dot size from what you said. I guess I should have known that. Simple math, if we have two given values and one value is (100%) we can cross multiply to get the other. DUH LOL<LOL So with my scope I'd be more percise by mentally dividing the subtension by 1/8ths rather than 10ths, because the dot is 1/4 the distance and the eye/brain will coincide with that. COOL BEANS!

I don't know if you looked at the new scope at Clearidge, the Ultra XP5. It's a 30mm tube with 5X optical zoom. The mil-dot subtends at .212, not really 1/5th but closer. I kind of like the 5X zoom and the side focus would be very handy. I'd like to try one.

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#66036 - 03/08/10 10:27 AM

Re: Drop compensation?? [Re: Tigger]

TCTex.
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Tig, Nikon makes a nice 4.5-14 X40 SF with a mil dot in it for under 300. I have one and it has been a good scope for the last 4 years. For what it is worth…

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