We often hear the term MOA; but what is MOA and what is it for? At Algatec Academy, we briefly explain this concept, which is essential for zeroing scopes.
What is MOA?
The definition of MOA starts with understanding the acronym: MOA stands for "Minute Of Angle." Therefore, MOA is an "angular measurement" that corresponds to one-sixtieth (1/60) of a degree. In other words, if we take one degree of an angle and divide it into 60 parts, each part corresponds to one MOA.
MOA at 100 meters
As a reference, the value of 1 MOA at 100 yards (91.44 meters) is equivalent to 1.145 inches. Adapting these values to our decimal metric system, the value of 1 MOA at 100 meters is equivalent to 2.9 cm (which is usually rounded to 3 cm). Since it is an angular measurement, its value varies in relation to the shooting distance. Thus, at 50 meters, its value will be half that of 100 meters: 1.45 cm.
- Approximate MOA values at different distances in meters:
- 1 MOA = 3 cm at 100 m.
- 1 MOA = 6 cm at 200 m.
- 1 MOA = 9 cm at 300 m.
- 1 MOA = 12 cm at 400 m.
- 1 MOA = 15 cm at 500 m.
Zeroing a Scope Using MOA
Below, you can see an image showing the relationship between the MOA value and shooting distances measured in meters, from zero to two hundred meters. Using this system, you will be able to effectively align your scope across multiple shooting distances.
Having these basic notions clear is fundamental for zeroing our scope, as shooting at 50 meters is not the same as at 100 meters. A good group at 50 meters can become a poor group when moved to 100 meters. Therefore, we must consider the distance according to the MOA so that the shots always hit the bullseye.
Achieving a good group is the desire of any shooter; however, depending on the intended use, we may require more or less precision. Logically, we cannot demand the same from a scope used for drive hunting a wild boar at a 60-meter run as we do from one used for deer stalking, where we might face shots at more than 150 or 200 meters.
How is a scope zeroed?
To adjust the distance to the target, the scope turrets are used. These are used to adjust the reticle's crosshairs for the distance at which we are going to shoot. These adjustments are made through each click of the turret, and each click or unit movement of the turret will correct the point of impact in relation to the MOA. This is how the scope's shooting distance is adjusted to ensure a better shot depending on how far we are from the target. To measure distances, a rangefinder or a Bushnell laser rangefinder can be used.
Typically, each click on a scope adjusts by 1/4 MOA; scopes for precision and long-range shooting "refine" this further, adjusting 1/8 MOA with each click.
Scopes that use the MOA system
For rifles and pistols, you can find a wide variety of scopes that use the MOA angular measurement to zero the optics to the desired shooting distance. Below are some examples of scopes with this feature, but you can find many more via this link to all scopes and optics.
Scopes with 2 MOA:
- AIMPOINT RED DOT SIGHT 9000SC 2 MOA
- AIMPOINT RED DOT SIGHT HUNTER H30L 2 MOA
- AIMPOINT MICRO RED DOT SIGHT
- H-2 2 MOA BLASER
Scopes with 4 MOA:
- AIMPOINT RED DOT SIGHT MICRO H-2 4 MOA
- AIMPOINT RED DOT SIGHT MICRO H-1 4 MOA
- AIMPOINT RED DOT SIGHT 9000L 4 MOA
- AIMPOINT RED DOT SIGHT 9000SC 4 MOA
Scopes with 6 MOA:
- AIMPOINT RED DOT SIGHT MICRO S-1 6 MOA
