MOA: General Information/Definition:
MOA (Minute of Angle or Minute of Arc) - a unit of angular measurement used in the firearms industry on scopes / firearms to define shooting accuracy
Calculating MOA for example (see diagram) is difficult and if you don't have time figuring it out - use a SCOPE CHART:
Diagram on how to calculate MOA or use a SCOPE CHART 
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MOA for Scopes:
A
shooter can easily readjust a scope
simply by measuring the distance in inches the bullet hole is from the
desired impact point on the target. Adjusting the MOA a certain number of clicks in the opposite direction depending on the measurement between the bullet hole and the target (bullseye) will help dial-in the accuracy of the scope.
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MOA for Firearms:
Please note: ideal conditions would be within an indoor range where the weather would not intervene with the projectile and with the use of a rifle vise or tripod.
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