Understanding Minute of Angle (MOA)
- A Minute of Angle (MOA) is an angular measurement
- A MOA is 1/60th of a degree.
- 1 MOA spreads about 1″ per 100 yards. (actually 1.047″)
- 1 MOA is a different size at different distances
- 8″ at 800 yards is still just 1 MOA
Becoming a Better Marksmen
1. Always think in increments of 1 MOA at whatever distance you are shooting.
For example, imagine you are shooting at 300 yards. You know that a MOA spreads out 1″ per 100 yards, so 1 MOA at 300 yards is 3″. Therefore, for your calculations at that 300 yard target, you should think in 3″ increments. By doing so, you can easily see that 2 MOA is just 2 of those 3″ increments, or 6″ total. And likewise, 1/2 MOA is 1/2 of those 3″ increments, or 1.5″.
If you are having trouble determining the increments in your head and would rather have a formula, you can try this method. Divide the distance (in yards) you are shooting by 100 and you will know how big 1 MOA is in inches. For example, imagine you are now shooting at 250 yards. 250 / 100 = 2.5. So, 1 MOA at 250 yards is 2.5″.
2. Determine how many 1 MOA increments will fit into the adjustment you are trying to make.
For example, imagine you are trying to adjust 8″ at 400 yards. You already know to think in 4″ increments for this example. Two 4″ increments (or 4″ chunks) fit into the 8″ of needed adjustment so you would need to adjust 2 MOA.
If you are having trouble doing this in your head and would rather have a formula, you can try this method. Divide the number of inches you want to adjust by number of inches in 1 MOA at that distance. For example, imagine you are now shooting at 600 yards and want to move the impact of the bullet 18″. You know that 1 MOA at 600 yards is 6″ from the previous step. 18 / 6 = 3. So, a 3 MOA adjustment at 600 yards will move the bullet 18″.
3. Think in MOA and not in “clicks” on your scope.
Although the majority of retail scopes adjust in 1/4 MOA per click adjustments, some scopes adjust in 1/8, 1/2 or even 1 MOA per click. Once you know how many MOA to adjust, you can then make the adjustments on your particular scope. For example, if your scope adjusts in 1/4 MOA per click, and you want to adjust up 2 MOA, you need to realize that 4 clicks adjust 1 MOA so you need 8 clicks total.
FORMULAS
- (Distance to target in yards) / (100) = inches per MOA at that distance
- (Number of inches of adjustment needed) / (inches per MOA at that distance) = MOA adjustment
- (Number of clicks per 1 MOA on scope) x (MOA adjustment) = adjustment in clicks on scope
- Note, if you insist on using 1.047″ per 100 yards instead of 1″ per 100 yards, you must multiply the (inches per MOA at that distance) by 1.047
References;
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