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I am into guns and shooting, more so pistols and shotguns than rifles. I shoot rifles a lot too but am certainly not into all of the nomenclature and other technical stuff about them. I have a lot to learn and my guess is that many others out there also have a lot to learn. I learned something new today, I learned exactly for what the abbreviation MIL stands for in MIL-DOT when referring to an optical rifle scope. Do you know what it means?

I don't think it was ever any big secret but I can tell you that an awful lot of people have gotten it wrong when telling me the meaning of Mil in Mil-Dot. Those folks have included other average shooters like me, long range marksman, high-power shooters, military types, SWAT type members, firearms instructors, gun dealers, and people I have met at ranges who had a Mil-Dot scope on their rifle. If you, like me, and the folks I just mentioned, thought it was an abbreviation for 'military', then you ought to visit the page at this link and enjoy a short but meaningful read about two terms: Minute of Angle and Mil. You might learn something new, I did. In fact, I learned two things, the meaning of Mil - and that while I knew what Minute of Angle meant, I probably could never explain it properly without notes in front of me.

All the best,
Glenn B
 

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A mil is an abbreviation for milliradian that is equal to 1 radian / 1000 (one thousand of a radian) . A radian is an angular unit of measure just like degrees is another.
One radiant is the length of an arc equal to the radius of a circumference. No matter how big the circunference is there are the
same nr. of radians in any circunference.
We know the lenght of a circunference is 2x pi x R. Therefore if we divide that length by the radius 2xpi x R / R we are left with 2xpi.
Pi = 3.1416 so Pi x 2 = 6.2832 ...therefore there are 6.2832 radians in a circumference. If we multiply this by 1000 we find there are 6,228.32 milliradiands (mils) in one circumference.

A simple way to look at this, lets imagine our shooting range and we are in the center of a bit circle and we have a circumference with a radius of 100 yards.
100 yards = 100x36 = 3600 inches.
So if we divide 3600 inches / 1000 (the 1thousand of a radian) = 3.6 inches.
That is why a milliradian equals 3.6 inches at 100 yards.

The mil dot can be an actual dot, a line or oblong that also helps estimate distance to a target. So the shape of that dot can be used for fine estimation. I think everyone refers to it as dot nevertheless but if you get into range estimation you will see how the different stadias in scopes
help in different ways and different levels of precision.
One could use any angle of measure (including MOA) to estimate any distance in any unit of measure but one needs to have a good idea of the
size of the object is trying to measure and the mean value of that value in the stadia you are using to calculate that distance. Mil-dot is pretty much the standard for doing that but MOA can be used too.
 

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1 mil = 1 meter @ 1000 meters
 

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Just to throw more info on the pile, devisions go as such:
Degree, minute, second, radian, mil

At least IIRC anyway.
In any event its kind of amusing how even though its a system of physical measurments its indicated in increments of time :)
 

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1 mil = 1 meter @ 1000 meters
Good point.
By using the same approach if we imagine a range of 100meters (a tad longer than 100 yards, precisely 109.3 yards)
100 meters / 1000 = .1 meters that is 10 centimeters at 100 meters in your paper target.
So assuming you have one tenth of click value in your mil scope every time you click you are doing 1 tenth of a miliradian so you are moving 1 cm. 1 cm = 0.4 inches. so with two clicks you are 0.08 inches (very close to the inch value of 1MOA at the 100 yards that is very similar distance)
The issue is that many scopes with mil-dot reticles also come with MOA turrets therefore the proper conversion is necessary.
It is up to the shooter what unit of measure he/she wants to use for distance, speed, etc.. but having alternative units is a good thing
for other people to understand that data.
 

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Just to throw more info on the pile, devisions go as such:
Degree, minute, second, radian, mil

At least IIRC anyway.
In any event its kind of amusing how even though its a system of physical measurments its indicated in increments of time :)
Trigonometry works best with degrees to keep formulas simple and use the standard functions available by default in the scientific calculators so in order to use the tangent calculation for example we need to convert to degrees. Anyway anything can be converted to anything as soon as they are in the same dimension. For me the metric system is best because I learned with it but have no problem in using and visualizing inches, feet, yards, miles ,etc..

I guess bottom line is, know your bullet, know your spreads, know your scope and how it adjusts and what the mean values are in the paper so when you go do other things you can actually rely on that data. Also know your targets so practice estimating distance even if it is by eye.Something can provide hours of fun while simply driving or walking.
 

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I am into guns and shooting, more so pistols and shotguns than rifles. I shoot rifles a lot too but am certainly not into all of the nomenclature and other technical stuff about them. I have a lot to learn and my guess is that many others out there also have a lot to learn. I learned something new today, I learned exactly for what the abbreviation MIL stands for in MIL-DOT when referring to an optical rifle scope. Do you know what it means?

I don't think it was ever any big secret but I can tell you that an awful lot of people have gotten it wrong when telling me the meaning of Mil in Mil-Dot. Those folks have included other average shooters like me, long range marksman, high-power shooters, military types, SWAT type members, firearms instructors, gun dealers, and people I have met at ranges who had a Mil-Dot scope on their rifle. If you, like me, and the folks I just mentioned, thought it was an abbreviation for 'military', then you ought to visit the page at this link and enjoy a short but meaningful read about two terms: Minute of Angle and Mil. You might learn something new, I did. In fact, I learned two things, the meaning of Mil - and that while I knew what Minute of Angle meant, I probably could never explain it properly without notes in front of me.

All the best,
Glenn B
So did everyone get a passing grade??
 

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Just to throw more info on the pile, devisions go as such:
Degree, minute, second, radian, mil

At least IIRC anyway.
In any event its kind of amusing how even though its a system of physical measurments its indicated in increments of time :)
And the reason for that is; Beuller?; Beuller?; Anybody?

Because the Earth is round, like a circle, and rotates around an axis. If you wanted to sail to where you were going, you needed to know where you were. Not easy in a sea whose only landmark was the Sun. You needed to know when it was exactly, which would tell you where you were, if not exactly, at least more or less. So you invented a system to divide up the Earth into latitudes and longitudes using degrees, minutes, seconds, radian, mil, etc., AND THEN you made a clock that kept time using the same mathematical system as descriptors, which you used with a sextant.

The terms used in clocks for denoting time, were adapted from the system of physical measurements that were used in navigation, among other things. Not the other way around.

I guess just felt like sharing.

Now don't get me started on Star Navigation!
 

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Makes total sense, 'specially when you throw rate of motion over time (as in 'speed')
 
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Folks who are new to the “community” often become fixated upon the whole stadia-metric range determination process using a graduated reticle.

Yes, determining the range to an object of known size can be done and it’s important to learn how and to become skillful at that task.

However, this method of range determination is seldom used in the field. A laser range finder is quicker and more accurate and there are seldom objects of known size in your sector.

The graduated reticle in the telescopic rifle sight is useful in many other ways. Learning those other skills are at least as important as determining range.

Some of those skills are:

Applying lead to or trapping a moving target
Applying hold off for wind
Applying a rapid correction hold for a second shot
Measuring wind velocity
Supporting shooter spotter dialog
Adjusting supporting fires
 

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Doesn't hurt to know that an average sized male person shaped target will width match (at shoulders) an A2 front sight post when in the 250m range and that such targets are roughly 3x taller than they are wide.
EG: half a sight post width +/-500m, 2/3 width +/-400, double width +/-125, etc.

Just in case there's no gizmonics to count on of course.
 
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Doesn't hurt to know that an average sized male person shaped target will width match (at shoulders) an A2 front sight post when in the 250m range and that such targets are roughly 3x taller than they are wide.
EG: half a sight post width +/-500m, 2/3 width +/-400, double width +/-125, etc.

Just in case there's no gizmonics to count on of course.
Don't put too much stock in the average size of humans.

Shown here are two adult Caucasian males of the same age.


Similarly, attempting to measure animate targets in the field is difficult to say the least. They have a tendency to move around and are fleeting, especially after the shooting starts.


In the above image the guy is at 870-yards and is walking across the road at a leisurely pace. Getting an accurate milradian measurement of him is impossible. Once you snap a still picture it gets easy.

Beyond the point blank range of your rifle an accurate range determination is important and the greater the range the more important the accuracy of that determination becomes because your rifle's danger space shrinks as range increases
 

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Shown here are two adult Caucasian males of the same age....
... with the one on the left being European, probably French, and the one on the right being a corn fed good ol' boy from down south USA :D
 
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Measuring wind velocity?? Please expound.
Stadia Metric Wind Velocity Determination;

Record the time it takes for something (tumble weed, newspaper, Styrofoam cup, smoke, dust, etc.) to cross a subtended angle (distance) then convert to velocity (distance/time).


In the above picture the range to the back of the house to be approximately 800-yards. A ten-mil span would equal 24-feet. Let's say a paper blows across that span of ten-mils in 4.5-seconds. The wind velocity would be 5.3-feet per second or 3.6-miles per hour.

This same technique can be used to measure the speed of a moving target (walking). This is great fun watching a guard walk his mount back and forth like a little metal duck in a shooting gallery.


There is a function for this in Field Firing Solutions Delta IV software loaded on my field computer. It even has its own stop-watch function.

You might ask yourself, "Who has time for this?"

Occupy a hide site for a couple of days and you'll see how much time you have to detail your range card and sector sketch. Since you've got to maintain situational awareness over your area of responsibility such exercises can actually be helpful. It also makes you a better wind reader.
 
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