Airgun Accuracy

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The Mildot, MRAD and the MOA for FT shooting

Just a thought about the measurements of Mil and MOA that every shooter with a riflescope uses and why it is confusing.

The Mil and Mildot

These days we see a lot of rifle scopes with a Mildot reticle. A lot has been written about it. But a lot of that writing is very mathematical and not very practical for every day use.

It helped me a lot to understand the Mildot thing when I realized that the word Mil comes from milli. Like in millimeter, milliliter or milligram. And milli means the 1000th part ( 1/1000 or 0.001).

So a mil  subtends 1/1000 of the distance. ( for instance 50 meters = 50 x 1000 = 50000 millimeters. 50000mm divided by 1000 is 50mm). More practical:

  • A mil at 50 meters distance is 50 millimeters.
  • A mil at 40 meters distance is 40 millimeters.
  • A mil at 30 meters distance is 30millimeters.
  • A mil at 10 meters distance is 10 millimeters.
  • And a mil at 34.5 meters is 34.5 milliters. You get this simple math it by now I guess.
Mildot Reticle

Mildot Reticle

And in a good mildot reticle the mil is the distance from the center of a dot to the center of the next dot.  This is true for fixed magnification scopes. But the mil is only a mil at a certain magnification in zoom scopes that have a second focal plane reticle (SFP or 2ndFP). In First Focal Plane zoom scopes (FFP) the mil is always a mil regardless of the zoom setting.

The MOA

Then there is the MOA or Minute Of Angle. Outside the riflescope business it is called the Minute of Arc but it is the same thing. And it has NOTHING to do with the Mil. Thats what makes things confusing. But the MOA is used used on almost every rifle scope produced for the graduation of the elevation and windage turrets (except those from Germany). The word Minute stands for 1/60th part (1/60 or 0.0167). The MOA is very close to 1 inch at 100 yards which is a handy and easy size when you want to adjust your scope AND understand imperial sizes. This is the reason the Imperial users and producers like the MOA and still stick to it.

In metric units the MOA makes no sense at all. This is because in metric sizes the MOA is 29.08 millimeters at 100 meters. And 29 mm is not an handy or easy figure to use for adjustments or calculations. Thats exactly the reason the USA military invented and use the metric Mil and Mildot reticles. Because it is metric and the US forces only use metric units like the meter, kilometer, liter and so on.

Scope turrets are usually divided in 1/4 or 1/8 clicks. In the imperial system that makes sense because they use these divisions of an inch a lot. And one quarter of an inch really means something to an imperial schooled person. But a 1/4 moa click on a scope turret is a quarter of 29.08 millimeter is 7.27 millimeter which is a strange figure to use for metric schooled persons.

The MRAD

So what does make sense to metric schooled people? The MILLIRADIAN, MILRAD or MRAD division on a scope turret. Because the MRAD is the same as the MIL. And thus 1 MRAD is 10 millimeters at 10 meters or 50mm at 50 meters. which is the same as 10 centimeter at 100 meters. Easy! Especially with Mildot reticles but also for any scope in combination with a metric schooled person.

A MRAD Scope that can be used for Field Target shooting is the Sightron SIII 10-50×60 LRMD-CM model (Long Range Mil Dot – CentiMeter). This scope has click divisions of 0.05 mrad. The click value of 0.05MRAD is 1/20th of 50 mm at 50 meters which equals to 2,5mm per click at 50 meters. Certainly fine enough for a 40mm hitzone at 5 meters.

I hope this helps some of you to better understand and remind the Mil and the Mildot so you can use them for everyday shooting.

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