 NPR2 Range Estimation 

02192003, 11:08 PM

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Join Date: Nov 2002
Location: California
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Re: NPR2 Range Estimation
Brent,
The reason that I show a .9 and a 1.1, is that each or those are paired with what would be the reading had the .25 dot been a .20 dot.
Like I said, when I have readings over 1.0mil, I disregard the .125 increments that a 1/8th division would give, and divide even 10ths.e.g.,1.1,1.2,1.3,..etc.
This is also why in the original post, I make mention of how I break it down into 1.15,1.65,etc.
Back to your original question, I show the difference between my way and the exact way. The difference is marginal, and in the field not and issue.
Hope this helps. Thanks
Marco
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02202003, 03:04 AM

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Re: NPR2 Range Estimation
Hey Luke,
Thanks for pointing out my reading comprehension. [img]images/icons/grin.gif[/img] This was almost puttin me in the nut house. [img]images/icons/grin.gif[/img]
I went back and reread the whole thing again and figured out how it worked.
Dropping the 1.25 mil to 1.0 was the first thing I forgot you did, then you threw in the constant, which I forgot how it worked using it, damn it's been a while. [img]images/icons/grin.gif[/img] Next all the .94 mil multiples with the third didget had my brain in sever pain when there wasn't ten of them [img]images/icons/confused.gif[/img] when I reread it I realized you were just breaking down the .75 mil section in between the edges of the dots, duuuuh! I assumed I understood what you were doing and missed a few things to say the least.
Anyway, thanks for prying my eyelids open. [img]images/icons/grin.gif[/img] You explained it very well, but you're right, the first formula was a bit confusing and having not used the constant 27.77 for a while I forgot what the hell to even do with it. [img]images/icons/rolleyes.gif[/img]
Ok here we are now, it's say 25 yards off at most, less when it falls in the middle of the .75 mil range.
Here's my thoughts on this now that I see the pros and cons, and I think the moa corallation question is of interest to you.
Each 1/10th mil is equal to about .36 moa, so if you used this to range a 30 inch target and it took 1.1 mil, this equals 3.96 moa. (11*.36 = 3.96) This would indicate 757 yards when the 30" target is divided by 3.96 moa. So I guess it comes down to which formual do you want to use, 1.1/833 = range or 30/(1.1*.36) = range.
I seems the .36 moa multiple wouldn't be as easy to add up in ones head like the multiple of .2 in the R2. Assuming you know the constant for the animal your hunting before hand, the 1.1/833 is a simpler calculation, not to do in your head, but simpler none the less.
What do you think?
It seems the 1/10th divisions equaling .2 moa is a little more precise than the .36 moa divisions of the mildot but I'm not sure if yours can be modified with a different power setting or not? What setting is it calibrated to range at, is it 10x?
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Brent Moffitt

02222003, 05:02 AM

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Join Date: Nov 2002
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Re: NPR2 Range Estimation
Brent,
Going back a bit just to align ourselves…
The best resolution I think the R2 reticle provides is .2 moa, or 1 tenth of a line. This is pretty easy to break down like this. The 1242x56 has the advantage of twice this resolution if set on 42 power and would be .1 moa. On 42x the lines are equal to 1 moa now not 2 moa.
When you speak of “a line” are we talking about 1moa or the 2moa spaced lines of the tick marks?
Is the 42x scope designed to read at another power setting, how come the “lines” are equal to half the value?
The method I use is to measure the animal and count the number of lines high, say 2.7 lines. I divide half the targets size by this number and move the decimal two places to the right.
I realize that you do this to give yourself (and the animal) a margin of era however, in your example of the 40” target; the chart is actually for a 20” target/vital zone, correct? If so, the 20” is actually a 10”.
That would make things much more impressive in my mind regarding the capabilities. Not looking close enough at your formula, I was going off of the prescribed NF formula that they use.
Given the fact that .05 mil is about .2 moa, that would be comparable to the NF 5.522 or 832, but again the 1242 would give double this resolution.
Please explain the whole difference in resolution comparison.e.g. what does the 22x,32x,and 42x read a 2 moa tick to tick division at full power?

When I initially broke this down, I started by breaking down a mil, which is equal to 3.444moa – 3.44 rounded.
I then divided that by 10 (same division used with the mil dot reticle .1mil reading) for a .34moa reading. .34moa = .1mil
If I break the mil down to .05 as you mentioned, I would see a .17moa (.2moa rounded. This .2moa should be easy to read as you said.
It may even be possible to break it down further like you said. Having not looked down behind one, I don’t know.
However, after speaking with the NF people, they seem to think that if I was breaking down the mil into .05 increments, that I should be able to break the moa down into .1..we’ll see.
Another realization that I now see, is that by having the 2 moa tick mark divisions, it is like having a reference point every .6mil on the mildot reticle. This is great!
It seems the .36 moa multiple wouldn't be as easy to add up in ones head like the multiple of .2 in the R2. Assuming you know the constant for the animal your hunting before hand, the 1.1/833 is a simpler calculation, not to do in your head, but simpler none the less.
What do you think?
I agree with you. I wouldn’t really use the mil reticle as a moa reticle. I would simply treat each as they are. Using the mil dot in the .1, or 1.5 increments and doing the math as usual is a good way to go.
The reality of the speed of your method is apparent when transferring into dialed or held corrections.
It seems the 1/10th divisions equaling .2 moa is a little more precise than the .36 moa divisions of the mildot but I'm not sure if yours can be modified with a different power setting or not? What setting is it calibrated to range at, is it 10x?
It is set for a 15x reading. However, tell me what your thinking. I have ranged using the 5x and simply multiplied by 3. I can also use the 10x and do the same.
Thanks,
Luke
nullnullGiven the fact that .05 mil is about .2 moa, that would be comparable to the NF 5.522 or 832, but again the 1242 would give double this resolution.It seems the .36 moa multiple wouldn't be as easy to add up in ones head like the multiple of .2 in the R2. Assuming you know the constant for the animal your hunting before hand, the 1.1/833 is a simpler calculation, not to do in your head, but simpler none the less. It seems the 1/10th divisions equaling .2 moa is a little more precise than the .36 moa divisions of the mildot but I'm not sure if yours can be modified with a different power setting or not? What setting is it calibrated to range at, is it 10x?The best resolution I think the R2 reticle provides is .2 moa, or 1 tenth of a line. This is pretty easy to break down like this. The 1242x56 has the advantage of twice this resolution if set on 42 power and would be .1 moa. On 42x the lines are equal to 1 moa now not 2 moa.The method I use is to measure the animal and count the number of lines high, say 2.7 lines. I divide half the targets size by this number and move the decimal two places to the right.Given the fact that .05 mil is about .2 moa, that would be comparable to the NF 5.522 or 832, but again the 1242 would give double this resolution.
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02222003, 05:04 AM

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Re: NPR2 Range Estimation
Sorry for the screw up on that last post. [img]images/icons/confused.gif[/img]
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02222003, 04:07 PM

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Re: NPR2 Range Estimation
Hey Luke,
Been working on some figures and reply off line, I'm kind of stumped over Nightforces suggestion on pg. 6 that at 3.5x the dots will give holdover points at 10, 20, 30 moa etc. From everything I can figure they would be 14.62 moa (or 4.25 mil) apart at 3.5x?
I see 5x as being real close to 10 moa spacing though, 10.32 to be exact.
Have you checked this suggestion of theirs?
There are plenty of errors in the manual of theirs, so this doesn't really surprise me, just thought I'd check it out though.
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Brent Moffitt

02222003, 05:48 PM

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Join Date: Jun 2001
Location: Palmer, Alaska
Posts: 2,539


Re: NPR2 Range Estimation
Brent:The best resolution I think the R2 reticle provides is .2 moa, or 1 tenth of a line. This is pretty easy to break down like this. The 1242x56 has the advantage of twice this resolution if set on 42 power and would be .1 moa. On 42x the lines are equal to 1 moa now not 2 moa.
When you speak of “a line” are we talking about 1moa or the 2moa spaced lines of the tick marks?
What I meant by this; Yes, a line/bar/tic, as you see it in the reticle is 2 moa spaced, so .2 moa equals 1/10th of a line.
And why I think the R2 only offers .2 moa resolution is this; I break the 2 moa lines down visually in half “first” (1moa), then I can only see to break each 1 moa down into 5 equal lines (.2 moa each), and if the target has really sharp edges “maybe” smaller, but unlikely on game.
If you really think about it, .1 moa pretty much equals 1/10th of an inch, this is what you’re trying to discern. This is hard enough to do at 22x with the imaginary lines already numbering 10, I just don’t think that I could discern 20 of them at 22x.
At 42x the 1/10th spacing does the same as dividing the 22x into 20 spaces, it just recalibrates the lines to nearly 1 moa to do it.
Is the 42x scope designed to read at another power setting, how come the “lines” are equal to half the value?
The 42x is calibrated for 2 moa spacing between lines at 22x, same as the 22x and 32x scopes. If you could turn the scope to 44x it would be exactly 1 moa spacing, but 42x would be very close. One always has 22x with it also to verify the 42x reading if in question or you couldn’t use 42x because of mirage or some reason.
Brent:The method I use is to measure the animal and count the number of lines high, say 2.7 lines. I divide half the targets size by this number and move the decimal two places to the right.
A previous example above for reference;
40" chest on this moose measures 2.7 lines tall. Half the chest size 20"/2.7 lines = 7.40 or 740 yards.
I realize that you do this to give yourself (and the animal) a margin of era however, in your example of the 40” target; the chart is actually for a 20” target/vital zone, correct? If so, the 20” is actually a 10”.
That would make things much more impressive in my mind regarding the capabilities. Not looking close enough at your formula, I was going off of the prescribed NF formula that they use.
A previous example below for reference again;
Brent:If you do the same thing using a 20" target (dividing by half that though) you'll see a much larger distance between the one tenth increments though.
Examples of other increments with a 20" target would be;
2.0 = 500 yards
1.9 = 526
1.8 = 555
1.7 = 588
1.6 = 625
1.5 = 666
1.4 = 714
1.3 = 769
1.2 = 833
1.1 = 909
1.0 = 1000
The vital zone size is not even considered here, I only use the animal’s chest depth to determine range (40”), the 20” “half size” used in the formula above, it is only to keep the formula correct. I am dividing lines and 1/10th lines now, not MOA like the NF formula uses. This gives smaller numbers to divide in your head this way.
The second chart, it was with a 20” chest, correct. I also use half this number (10) in the formula as well. I only used this to contrast the 40” chest chart, and show how the target size influenced the total range between each 1/10th increment. You’ll see how the range between 1.1 and 1.0 above is over 90 yards. At the same range on the 40” chest chart it is less than 50 yards. I look for the range that keeps each less than 30 yards really. The drop between each increment is too great for me to take a shot if it isn’t.
I hope that clarifies the ranging and formula aspects a bit. Let me know if I left something out.
Brent: Given the fact that .05 mil is about .2 moa, that would be comparable to the NF 5.522 or 832, but again the 1242 would give double this resolution.
Again, all three are calibrated at 22x, the 42x setting obtainable with the 1242x scope will “almost” make the line/bar/tics at 1 moa spacing by way of increasing the target size to double what it was.
Please explain the whole difference in resolution comparison.e.g. what does the 22x,32x,and 42x read a 2 moa tick to tick division at full power?
Refer to above.

When I initially broke this down, I started by breaking down a mil, which is equal to 3.444moa – 3.44 rounded.
I then divided that by 10 (same division used with the mil dot reticle .1mil reading) for a .34moa reading. .34moa = .1mil
You are correct, it is specifically .34 not .36 moa as I had generalized.
If I break the mil down to .05 as you mentioned, I would see a .17moa (.2moa rounded. This .2moa should be easy to read as you said.
It may even be possible to break it down further like you said. Having not looked down behind one, I don’t know.
15x might be a limiting factor in sizing up the animal to that degree, maybe, just a guess.
However, after speaking with the NF people, they seem to think that if I was breaking down the mil into .05 increments, that I should be able to break the moa down into .1..we’ll see.
I think it just depends on how small it is on the target, by that I mean, are you trying to split in half a ½”, ¼” or what, and is it even feasible to do given the situation and distance.
Another realization that I now see, is that by having the 2 moa tick mark divisions, it is like having a reference point every .6mil on the mildot reticle. This is great!
True. Wouldn’t it be even nicer yet if they had a smaller tick mark at the 1 moa point? That would help out visualizing the 5 ticks between each 1 moa line then.
Brent:It seems the .36 moa multiple wouldn't be as easy to add up in ones head like the multiple of .2 in the R2. Assuming you know the constant for the animal your hunting before hand, the 1.1/833 is a simpler calculation, not to do in your head, but simpler none the less.
What do you think?
You posted earlier; [B] Reading other posts about the NPR2, there was mention of it working best as a calibrated hold over reticle if the velocity was up around 3300+fps. I am only humming along at around 3000fps (.300WM). Realizing that, the benefit I was hoping for was that I was thinking about speaking in the same moa language of the turrets. This would eliminate some extra thinking for the shooter I would think.
I was thinking back on that part there and it didn’t seem it would help you much, if that’s what you meant by... speaking the same language and such.
I agree with you. I wouldn’t really use the mil reticle as a moa reticle. I would simply treat each as they are. Using the mil dot in the .1 or 1.5 increments and doing the math as usual is a good way to go.
Probably the fastest using the mildot is the way you are, like you say.
The reality of the speed of your method is apparent when transferring into dialed or held corrections.
Also, the ability to do the range formula in your head quickly has an advantage. [img]images/icons/wink.gif[/img]
Brent:It seems the 1/10th divisions equaling .2 moa is a little more precise than the .36 moa divisions of the mildot but I'm not sure if yours can be modified with a different power setting or not? What setting is it calibrated to range at, is it 10x?
I was only thinking that if the NF manual says you’re dot spacing is 10 moa at 3.5x, it would be 3.6” approximately at 10x. This would leave you the ability to power up to 15x and vary your spacing a little tighter possibly at an even moa. I figured it wrong though. It would go 10 moa at 3.5x, 5 moa at 7x and 2.5 moa at 14x instead.
If it is indeed 10 moa per dot spacing when it’s set at 3.5x, it would be 2.5 moa at 14x, this is still wrong and can’t be 10 moa spacing at 3.5x if it is calibrated for “1 mil” at 15x. Considering when mine is set on 5.5x, a 1” square will be 4” and at 11x it will be 2”.
It is set for a 15x reading. However, tell me what your thinking. I have ranged using the 5x and simply multiplied by 3. I can also use the 10x and do the same.
That works for me. [img]images/icons/smile.gif[/img] Are the mils spaced exactly 3.6” at 100 yards on 15x? What are they spaced at set on 3.5x?
Take care,
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Brent Moffitt

02242003, 07:06 PM

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Join Date: Nov 2002
Location: California
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Re: NPR2 Range Estimation
Brent,
15x might be a limiting factor in sizing up the animal to that degree, maybe, just a guess. I think it just depends on how small it is on the target, by that I mean, are you trying to split in half a ½”, ¼” or what, and is it even feasible to do given the situation and distance.
I aggree, that would be the best situation, conditions optimal. Like I had mentioned, there is no problem reading in the 20ths readings ,e.g.1.5,1.55,2.,2.5,2.55,etc.With practice. It does depend on the visability/weather/target though.
Luke Realizing that, the benefit I was hoping for was that I was thinking about speaking in the same moa language of the turrets. This would eliminate some extra thinking for the shooter I would think.
Brent I was thinking back on that part there and it didn’t seem it would help you much, if that’s what you meant by... speaking the same language and such.
I was thinking that it would be a lot easier to hold over or dial in your corrections using the same correction language that say your spotter might give you (mil), without having to do the math of converting the mils to moa for the dialed in corrections. [img]images/icons/smile.gif[/img]
I was only thinking that if the NF manual says you’re dot spacing is 10 moa at 3.5x, it would be 3.6” approximately at 10x. This would leave you the ability to power up to 15x and vary your spacing a little tighter possibly at an even moa. I figured it wrong though. It would go 10 moa at 3.5x, 5 moa at 7x and 2.5 moa at 14x instead.
I was told by the NF people that at 15x the mil will read 3.66" @ 100yds. They also mentioned that for the best readings, you should go to the 100yd line and see what the mil subtends at using the different power settings.
Their math came out to 10.98moa using the 3.5x setting? Could you show me the math that you used to get your answers? [img]images/icons/confused.gif[/img]
They also mentioned, that if you half the power value, you end up doubling the 1mil spacing.e.g.,7.5x = 2moa
True. Wouldn’t it be even nicer yet if they had a smaller tick mark at the 1 moa point? That would help out visualizing the 5 ticks between each 1 moa line then.
Yes it would. Perhaps in the future, such a division will exist. Your other idea of the ideal R2 was also good....[b[A custom modified R2 I'd like to see would add bars placed at 1 moa increments being 1 moa wide instead of 2, with bars placed at .5 moa increments being .5 moa wide and this one being a finer line as well, .1 moa width would be good.[/b]
I will be looking forward to switching out my mildot reticle for the NPR2.
If you have more info on things you have done with your R2..e.g. adjusting the power settings for specific holds..etc, I would be interested.
Luke
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