Imagine you went to a gun shop to pick up your favorite rifle and a rather expensive scope to pair along. Now, you are in the field to have some fun shooting. You set up a beer can as your target at 150 yards. But when you shoot, your bullet does not hit your target and strikes somewhere below the mark. Here, Moa comes into play.
If you are into shooting, you must have heard that Moa is used to adjust rifle scopes. For a good shooting experience, you must understand what Moa is and how it plays a role in improving your shooting accuracy. The following article will give you an easy explanation of Moa and how it works, so you don’t miss your target the next time you go out shooting.
What does Moa stand for?
MOA stands for Minute of Angle.
A minute, in this case, is the 1/60th part of a 360-degree angle. For understanding it better, consider a circle. A circle has 360 degrees. Take one degree out of 360 and then divide it into 60 parts. In this way, you get the 60th part of 360. Although it is a tiny part, it makes a huge difference in accuracy when hitting your target. Even the tiny shift in angle can make you miss the mark. Hence, for accuracy, you need to adjust your MOA to the correct angle or minute.
One minute or 1 Moa is equal to 1 inch at 100 yards. In actual mathematical terms, 1 minute of an angle equals 1.047 inches, but shooters use 1 inch for convenience. However, it becomes applicable in a long-distance shooting.
Why do we measure in minutes?
When a bullet leaves the barrel, it does not travel in a straight line; instead, it is pushed downwards by gravity. Due to gravity, the bullet moves in an arch-shaped trajectory. The velocity of a bullet decreases as it moves to longer distances; thus, gravity affects it more. When you take a shot, the bullet does not hit the target that you have aimed; it would instead hit below it. The difference between your target aim and the place where the bullet hits are called bullet drop. This difference is measured in inches. We measure shooting in minutes to compensate for bullet drop.
MOA and Distance
MOA is an angular measurement. For this reason, it can calculate angles between two things and not the length. For measuring the distance, we need to translate it into a linear measurement. We require some basic math to do that.
If we break down 1 minute of angle, then 1 minute is one inch, and angle is yards. So, 1 minute of angle is calculated by 1 inch at 100 yards. When you make a one-minute adjustment on your scope, there is a one-inch change in where your bullet strikes the target.
The inches increase with the increase in yards. If 1 inch at 100 yards is 1 MOA, then 2 inches at 200 yards is 1 MOA, 3 inches at 300 yards is 1 MOA, and so on. If you take your aim at 100 yards and it falls two inches below the target, it would require an adjustment of 2 MOA.
Consider the following table for better understanding:
|Distance in yards||Change in 1 Moa|
We can also calculate 1 Moa at less than 100 yards with the same method. If 1 Moa is 1 inch at 100 yards, with half the distance at 50 yards, it is ½ inch. At 25 yards, it is reduced to ¼ inch.
Calculating 1 MOA size at your distance
You can use a simple formula to know what the size of Moa is at your particular distance. For this, divide your distance by 100, and you will get your 1 MOA for that specific distance.
300/100= 3 inches
400/100= 4 inches
600/100= 6 inches
Now, we will calculate Moa using 1.047 inch measurement
300 x 1.047/100= 3.141 inches
400 x 1.047/100= 4.188 inches
600 x 1.047/100= 6.282 inches
Determining 2 MOA
One thing you need to understand is 1 Moa is different at different yards. But what’s 1 inch at 100 yards and 2 inches at 200 yards is still 1 Moa.
We will now similarly determine 2 Moa. You know that at 100 yards, 1 Moa is 1 inch. So, at 100 yards, 2 Moa is 2 inches. Practically speaking, if you hit your target at 100 yards, and it drops by one inch, you will adjust 1 Moa on your scope to hit the target.
But when your target drops 2 inches at 100 yards, this is when you will adjust 2 Moa on your scope, which is 2 inches.
What about 200 yards?
Similarly, at 200 yards, 1 Moa is 2 inches. So, if at 200 yards, your bullet drops 2 inches, you adjust 1 Moa on your scope, and when your bullet drops 4 inches, you need to adjust 2 Moa on your scope.
Here, you can analyze that 2 Moa is different at two different ranges.
How to determine the bullet drop?
By adjusting the bullet drop, you can get better accuracy. To solve the bullet drop, you need first to know how you can determine it.
Imagine that you are shooting at 200 yards. When you hit the target, your bullet drops 30 inches from your desired target. The information you already have is that one Moa is 3 inches at 300 yards.
You will get your required Moa by simply dividing the bullet drop inches with the MOA inches at your distance. For calculating a 30-inch bullet drop at 300 yards, use this simple formula.
Bullet drop inches / MOA inches at a certain distance = Moa needed
30 inch bullet drop/ 3 inches = 10 Moa
Now, use a similar formula to calculate the required Moa for 400 yards with a bullet drop of 40 inches.
40-inch bullet drop/4 inches = 10 Moa
You need 10 Moa adjustments with your scope to compensate for a 40-inch bullet drop at 400 yards and a 30-inch bullet drop at 300 yards. In this way, you will be able to hit your target at the right spot.
How to translate Moa on turrets?
Now you know that 1 Moa is 1 inch at 100 yards, 2 inches at 200 yards, and 3 inches at 300 yards. The next thing you need to know is what does Moa mean on a scope. For this, you will need to assess how many Moa you need to adjust on your particular scope to make it more accurate.
Most retail scopes adjust in ¼ Moa per click adjustments; some adjust in ⅛, ½, and even 1 Moa per click. If your scope adjusts ¼ Moa per click adjustment, then it means then you need to click four times to get one Moa. If you want to adjust 2 Moa, you will click 8 times.
If you apply the same method with a 1/2 Moa adjustment scope, you must click 2 times to get 1 Moa. Hence, for adjusting 2 Moa, you will need 4 clicks.
|⅛ Moa||8 clicks equals 1 Moa|
|¼ Moa||4 clicks equals 1 Moa|
|½ Moa||2 clicks equals 1 Moa|
|1 Moa||1 click equals 1 Moa|
Essential Tips for Using Moa
Start by thinking in increments of 1 Moa
Imagine you are shooting at 800 yards and your bullet hits 16″ down from the target. To fix this, you need to adjust the bullet drop. Your first step should be to think in increments of 1 Moa. Here, 1 Moa at 800 yards is 8″, so think in 8″ increment for this particular case.
Calculate how many increments of 1 Moa will fit into your adjustment
You want to solve the 16-inch bullet drop, so two 8 inches increments will fit into it. For this, we will adjust 2 Moa.
Think in Moa while adjusting the scope
While adjusting your scope according to your desired results, you need to think in Moa and not clicks. Every scope has different specifications. Your specification range is 1/8, 1/4, 1/2, or 1 Moa per click.
Now assume that your scope adjusts 1/4 Moa per click, then this will mean that 4 clicks will adjust 1 Moa. Now, to adjust a bullet drop of 16 inches at 800 yards, you need to have 8 clicks to get 2 Moa.
Example problems and solutions
By now, you should be able to calculate Moa. Here are some questions related to it. Try to answer the following questions to check your knowledge. For simplicity, we have restricted the questions to 200 and 400 yards.
Problems for 200 yards
How many Moa is 2 inches at 200 yards?
At 200 yards, 2 inches is 1 Moa. You already know that at 100 yards, 1 inch is 1 Moa, and we also know that Moa is an angular measurement, so its linear size increases as we increase the distance.
How many Moa is 4 inches at 200 yards?
As 2 inches is 1 Moa at 200 yards, 4 inches will be the double, i.e., 2 Moa.
How many Moa is 3 inches at 200 yards?
Again, 2 inches is 1 Moa at 200 yards, so 3 inches will be 1.5 Moa.
If you adjust 4 moa on your scope, how far will a bullet impact change at 200 yards?
What we already know is that 1 Moa at 200 yards is 2 inches. So, if you adjust 4 Moa at the scope, your bullet impact change at 200 yards will be 8 inches.
If your scope adjusts 1/4 moa per click, how many clicks do you need to move 2 inches at 200 yards?
If a scope adjusts ¼ Moa per click, then it means that you need 4 clicks for 1 Moa adjustment. We already know that for moving 2 inches at 200 yards, you need to adjust 1 Moa. So we need 4 clicks.
Problems for 400 yards
How many Moa is 4 inches at 400 yards?
At 100 yards, 1 inch is 1 Moa. Remember that Moa is an angular measurement, and its linear size increases when the length increases. So, at 400 yards, 4 inches is 1 Moa.
How many Moa is 6 inches at 400 yards?
At 400 yards, 1 moa is 4 inches, and 2 Moa is 8 inches. So, 6 inches is half Moa added to 1, i.e., 1.5 Moa.
If you adjust 5 Moa on your scope, how far will a bullet impact change at 400 yards?
As we have established already that 1 Moa is 4 inches at 400 yards, so if you adjust 5 Moa on your scope, you will have a bullet impact of 20 inches.
If your scope adjusts ½ moa per click, how many clicks do you need to move 12 inches at 400 yards?
A scope with ½ moa adjustment per click means you need to click twice to get 1 Moa. Now, at 400 yards, 4 inches is one Moa, so if we want to move 12 inches, we need 3 Moa. We need 6 clicks to get 3 Moa.
Shooting is not just about buying the most expensive rifle or scope; it is also about getting accurate shots. For getting good accuracy, you need to learn Moa.
I hope that you find this explanation of Moa useful. Now that you understand what Moa is and how you can use it to compensate for your bullet drop, you are more likely to take accurate shots at your target. Use the above calculations to make the necessary tweaks in your rifle and enjoy a perfect shooting experience.