Home Forums Hunting & Shooting Long Range Hunting Meters and mils; Elegant Math... Please explain again...

The tangent of 1 mil is 1 Correct?
The tangent of 1 miliradian is .001 Correct?

Where does the elegance of meters come in to play?

I am thinking of retraining my head to go mil mil meters and just forget my misspent youth and moa yards. Just jump in with the foreign/commie-plot-math and hold my nose and do it.

They say it is a persihable skill and I admit that my brain cells are perishing.

The continuance of the decimals is the elegance.

Example:

1 mrad = 1 meter at 1000 meters
.1 mrad = .1 meter at 1000 meters = 1 dm = 10 cm = 100 mm

1 mrad = .1 meter at 100 meters = 1 dm = 10 cm = 100 mm
.1 mrad = .01 meter at 100 meters = .1 dm = 1 cm = 10 mm

1 mrad = .675 meter at 675 meters = 6.75 dm = 67.5 cm = 675 mm
.1 mrad = .0675 meter at 675 meters = .675 dm = 6.75 cm = 67.5 mm

an so forth.

Thank you very much for the reply! I think we have both tossed up some flawed data here in the first two posts.

I meant to say that the tangent of 1 radian is 1.
the tangent of 1 mil-radian is .001

Here is a paragraph from some website I just quicly cut and pasted:

"Using MRAD simplifies the math quite a bit. The tangent of one milliradian (0.001) is only very slightly larger than 0.001, so we don’t really need to find the tangent. One MRAD is therefore the ratio of the object size to its distance (a simple 1 to 1000 ratio). Therefore, at 1000 yards, an object measuring one milliradian (or one mil dot) is exactly one meter in height. To further simply the math, especially for distances well inside of 1000 meters, we can use millimeters for the object size. This gives us a 1:1 ratio in millimeters of object size to meters of distance. So at 1 mrad, a 100 mm object is 100 meters away, and a 750 mm object is 750 meters away."

MAN! I am not a math whiz... the tangent of 1 radian is 1.5574 approx.

I am lost....

Truth told. My apologies. I did not want to add to any confusion...

In a nutshell - forget about the tangent.

At any distance, no matter what unit it is measured in, 1 mrad is 1/1000 of this distance in the same unit.

1 mrad @ 1000 yards = 1 yard
1 mrad @ 1000 inches = 1 inch
1 mrad @ 1000 meters = 1 meter

hence

1 mrad @ 675 meters = .675 meters or 67.5 cm

So - to go to demonstrate the elegance of metrics:

You laser your target at 675 meters.
You know, your bullet will drop 341 cm at that distance.

To find out, how many clicks (.1 mrad) this is going to be, you need to understand, how much 1 click will bring POI up.

As seen above, this will be 6.75 cm.

341 cm / 6.75 cm = 50.5 --> 51 clicks = 5.1 mrad

Tyan Kleckner at NSSF has some great videos.

This one does MRAD

https://www.youtube.com/watch?v=S5AGsHSIsVo

I willingly admit I run mil with yards and it is no big deal. I know some will espouse that if you run mil you have to run meters but it has not been an issue for me.

I do know that once you go mils in a FFP scope measurements become somewhat useless. I do not know the drop in inches or cm and then convert it to mils, my 600 yard dope is simply 6.1 mil for elevation and .65 for every 5mph of wind. Even corrections are given in mils and it is extremely quick. I do not need to guess and say "about 6" low and 12" left". I simply say "impact .3mil low and .6 mil left".

Piss on the metric system. miles

^ This… What Varmint said.

You are way over thinking this. All you need to know is what your ballistic computer or dope card gives you for your drops and wind hold, and use your reticle to measure your miss and correct from there. By using the inches and trying to do math to convert it, all you are doing is adding a lot of opportunity for error and wasting time. That reticle is a ruler and gives you all the info you need.

When you do it this way, you can range in whatever the hell you want as long as your dope card is referenced the same.

+1.

Because they do not know what they are talking about. There is zero issue with using mils and yards. It's just a number.



Robert,


Don't over think it. It's just a number that is applied to your turret or reticle. Think only in mils. Do not think in inches, clicks or anything else. Print the drop chart in mils and just dial it on the scope. When you miss or need to correct use the reticle as a ruler and adjust.

What they said!

I am no math wiz, and I switched from m.o.a. to mils in one afternoon. Plug your rifles info into a ballistics calculator, and go shoot. Fine toon as needed. Mils are just a unit of measurement. No different than moa as another

The reason that is so, while the .001 to .001 correspondence is pretty close, is tangent is not a linear function. It's a ratio of sine divided by cosine. For small values of the argument, sin(Θ) is approximately Θ, while cos(Θ) is approximately 1.

You can also observe this from the Maclaurin series for the tangent function, where all terms after the first are quite small for small values of the argument.

But when you increase the angle, the later terms in the series become more influential.

None of any of what you guys posted in those first few posts matters. Make a dope card in MILS and shoot. Meters, yards, whatever distance doesn't matter. Dial your elevation, hold your wind and shoot.

So!

Mr. Mathman is the ONLY honest broker amongst us all! Everybody else is cheating!

McLaurin series... HA!

But seriously; thanks y'all. No denying I have always gotten wrapped around the axle down in the weeds of the details.

Nobody is range estimating with the mil's anymore?

I can see where meters are a good system to get pickled in if you get it more or less in your head and you use UTM grid topo's for long distance range estimation

http://sliderulemuseum.com/SR_Course.htm

NO ONE is allowed to go long range without first mastering the use of such said device as linked herein ye.

In my high school physics class there was a giant one hanging above the chalk board for instruction purposes. HA!

Took us to the moon back in the day.

Yup, and I think short-sleeved shirts with clip-on ties and black framed glasses are making a comeback.

you forgot pocket protectors.....

How's Apollo doin? Went to the range Saturday. Rocky and Adrienne are doin' just fine.

Polly is resting.