Milliradians: Definition
‘These are small. But the ones out there are far away.’
Give yourself a thumbs-up and hold it out at arm’s length. Congratulations! You’ve just measured two degrees of arc with the width of your thumb.
Now raise your hand and hold it out at arm’s length. Spread your fingers all the way. Brilliant! With the span between the tip of your thumb and pinky, you have measured 300 milliradians.
Degrees of arc, the kind you use routinely from your compass, are relatively imprecise compared to milliradians, mrad or mils. Remember, the width of your thumb is already one or two degrees. You can’t easily go smaller without chopping your body to bits for MOA, minutes of arc.
The width of a finger in mrad is closer to 20 to 30.
More specifically, where a circle is 360°, it is also 6400 mrad. This gives us a conversion factor of 17.77, or close enough 18. You can be 18 times more precise using mrad than degrees! This is why we use them for marksmanship and artillery.
Your real-world hands are great tools for remarkably reliable rule-of-thumb estimations. In Arma, much more accurate (and immediately usable) tools to measure mils include your compass, binoculars, rifle optics and spotting scopes.
