MOA, or Minute of Angle, is one of the most essential terms in rifle shooting. It is also one of the most misunderstood. But do not worry. We are here to help you understand the fundamentals of MOA.
What is MOA?
MOA is short for Minute of Angle. So, what is a Minute of Angle? The simple answer – 1/60th of an angle, but that doesn’t give you too much information, so let’s break it down.
A circle is 360 degrees. An angle is one degree of that circle. A minute of angle is 1/60th of 1 degree. In shooting, this measurement is used to adjust scopes, sights, and points of impact relative to the center of a target.
Still confused? Don’t worry; it will become more apparent. Just remember, it is an angle, not a distance.
MOA Fundamentals
Why is it important?
Although MOA is not a distance measurement, it can be used to determine distance when shooting. More specifically, it is used to determine the length from the center of the target. How is this possible? Remember that angles spread out in a cone-like pattern. More importantly, it spreads at a constant amount that is always the same at a particular distance.
For example, at 100 yards, the spread is approximately 1 inch and increases approximately 1 inch every 100 yards. So, at 100 yards, 1 MOA is about 1 inch. At 200 yards, 1 MOA is about 2 inches, and so on.
In shooting, you will use MOA to adjust sights or scopes and make aiming corrections as target distances change. More on that later.
What are common mistakes?
There are a couple of common mistakes regarding MOA that, if made, can drastically affect your accuracy.
- MOA is not 1”. MOA is 1” at 100 yards. Remember, it will increase or decrease as the range becomes longer or shorter.
- MOA is not a measurement of distance but a measurement of angle. It can be used to determine length from the center of the target but is still not a distance measurement.
- MOA and MILS are not the same. MILs, or milliradian, are also a measurement of angler but are based on 3.6” at 100 yards. 1 MIL equals 3.6 MOA.
How to use MOA
Now that you understand MOA (sort of), it is time to learn how to put it into practice.
You will first use MOA when sighting in a rifle or scope. When you shoot your first group, it will probably not be dead center. It will be high/low, left/right of center. By measuring the distance from this group to the center of the target and knowing the range from your position to the target, you can make the adjustments necessary to hit the center of the target.
For example, you are shooting a target at 100 yards, and your rounds are 3” high & 2” right. This means you need to move your point of impact 3 MOA down and 2 MOA left. If that same target were 300 yards, you would need to move your point of impact 1 MOA down and .6 MOA right.
To make the necessary adjustments, you need to know the specifications for your optics and how many clicks on the windage/elevation dials equals 1 MOA. The most common measurements are either one click equals 1/4 MOA or one click equals 1/2 MOA. Some long-range scopes may even use 1/8 MOA per click. Yes, it differs depending on the specific scope, but never changes on that scope.
With a 1/4 MOA scope, you will need four clicks to move the point of impact 1”. A 1/2 MOA scope will only need two clicks to move the point of impact 1 MOA. But the 1/8 MOA scope will require eight clicks to move the point of impact 1 MOA.
In target shooting, making MOA adjustments allows for precise accuracy; often, the difference between a nine ring or the X. Hunters generally do not need the same precision, just the ability to hit the kill zone. However, MOA adjustments may be necessary to compensate for bullet drop, especially when hunting with more extensive, slower caliber rounds such as the .45-70 or .450 BM.
MOA’s Role in Long-Range Shooting
Long-range shooting is where MOA becomes a more significant factor. As distances increase, especially out at 1000+ yards, even the slightest change can result in being feet off target. Wind, bullet drop, and even humidity can drastically change your point of impact.
If you know how those factors affect your round, you can use MOA adjustments to counter those factors. For example, what would the MOA adjustment be if shooting a target at 1000 yards and the bullet drop is 6”?
1 MOA equals 10” at 1000 yards; therefore, 6” equals 0.6 MOA. On a 1/2 MOA scope, this would be 2 or 3 clicks.
Summary
Now that you understand the fundamentals of MOA, you will better know how to adjust your optics, making you a more accurate shooter and ethical hunter.