In the shooting game, MOA stands for minute of angle.(I believe that mathematicians prefer minute of arc. but it amounts to the same thing) As you may remember from your math classes, one way that angles are measured is in degrees, 360 making a complete circle. Each degree can be divided into 60 equal parts called minutes, and each of these minutes can be divided into 60 equal parts called seconds. Simply put, if we are talking angles, a minute is a sixtieth of a degree.
If we were to draw an angle, that was equal to one minute of angle (or for that matter any angle that was less than 180 degrees), the distance between the lines would increase as the distance from where they met increased. The gap at 200 yards would be twice that at 100, and at 300 three times, and so on.
To get an idea of how one calculates how much a minute of angle is at a distance of 100 yards, first imagine yourself at the center of a circle that has a radius of 100 yards, or 3,600 inches. First we double the 3600 inch radius to get the diameter ,7,200 inches, and then multiply that by Pi, which to two places is 3.14 which gives us the circle's circumference, 22,619.47 inches. Dividing this by 360 gives us the width (technically the length of the arc) of a degree at 100 yards of 62.83 inches. Dividing that by sixty gives us the width of one Minute OF Angle (MOA) 1.05 inches. It is common to pretend that a MOA is equal to an inch at 100 yards, twice that at 200, three times at three hundred, and so on, and in truth this slight rounding off only amounts to a half inch at 1,000 yards, an insignificant amount.
The short answer to your question in that the program is telling you to move your scope adjustment four whole numbers and three of the divisions between the numbers. This would give a change in point of impact of approximately 4.75 inches at 100 yards, 9.5 at 200, 14.25 inches at 300 and so on. By giving your adjustment in the same units as your scope adjustments, your program saves you the chore of converting inches at some distance to MOA before adjusting your scope.
If anyone reading this sees that I have screwed any of this up (while eating my asparagus, corn on the cob,and barbequed chicken), jump in with your corrections. I do not suffer from the delusion that I am anywhere near perfect. Now back to the chicken.
