How to calculate the size of 1 MOA at range X.
The circumference of a circle can be calculated using these formulas:
So let us consider a circle in which you are the center and the radius is the range to the target. In this example, let's say the range is 400 yards (which is 14 400 inches). The circumference is:
Since 1 MOA is 1/60th of 1°, 1 MOA at 400 yards will be the circumference divided by 360 (number of degrees per circle), divided by 60 (number of minutes per degree). Therefore:
How to calculate the size of 1 mil at range X.
Use the same circle formulas. So for a range of 400 yards, the circumference is:
Since 1 mil is 1/6400th of a circle, divide the circumference by 6400. Therefore:
Here are the calculated values for ranges 100 to 1000 yards:
|Range||1 MOA (inches)||1 mil (inches)|
To simplify calculations, used MOA sizes are 1,2,3,4,... Mil sizes are 3.5, 7, 10.5, ...