Minute of Angle (MOA) - This is a constant measurement. One minute of angle is equal to one inch at one hundred yards. 1 MOA is equal to 5 inches at 500 yards. When someone brags that his rifle is capable of sub MOA groups, he means that his rifle will fire a groups that is smaller than one inch at one hundred yards, or less than 3 inches at 300 yards, and so on).

It stands for "minute of angle". Im no expert and im sure ill get corrected but ill give you something to chew on at least. One minute at 100 yards is equal to one inch. Therefor if you have a rifle that shoots perfect "MOA" it will shoot a one inch group at 100 yards, or a 1/2" groupe at 50 or a 2" group at 200yds. Thats about the best i can do, like i said some wizz kid will chime in and shoot you a bunch of technical BS.... ect.. Have a good one man!

Minute Of Angle. 1/60 of a degree. It is approxamitly 1" per 100yd (actualy it's 1.037"/100yd), so 1/2" @ 50yd and 6" @ 600yd are both 1MOA.
Groups are measured from center to center of the 2 furthest holes (outside to outside minus 1 bullet diameter is the same thing) and than converted to MOA

A simpler way to accurately measure center-to-center spread of a group on target is to measure from the inside edge of the farthest of the outside holes to the outside edge of the hole farthest from it. Same measurement as C-to-C, no guessing or math necessary.

Surbat6
That's the easiest way, until you run across a 22LR 5 shot group thats the size of a 30cal bullet hole No, I didn't fire the group, but the guy that did was shooting my 44US@ Mossberg (The Gopher Wrecker) while I watched. Groups from his Anshutz(sp) looked more like 243 bullet holes.

That's the easiest way, until you run across a 22LR 5 shot group thats the size of a 30cal bullet hole

The easiest way to measure one ragged hole , is to measure outside to outside and subtract 1 bullet dia. If you are shooting a 22 cal then you would subtract .22 from your outside to outside measurement.

MOA = minute of arc
360 degrees = full circle, 1 degree = 60 minutes, 1 minute = 60 seconds

think of the radius as a cone from 0 degrees to 45 degrees. the farther away from the center/point of the radius to the diameter of the arc the farther apart the point of minutes becomes. (=1 inch @ 100 yds & 3 inches @ 300 yds).

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We normally think of it as 1". The value of 1 MOA @ 100 yards is 1.047 inches. Here is a link explaining it, and how to use it to adjust your scope. http://riflestocks.tripod.com/moa.html

and while we're all bein real smart, I wanna play too, lol! Sometimes people will say, "I dont care about MOA; I only care about Minute Of Man." I always see that one as something that doesn't quite make sense because the minute determines the measurement of the arc; it should be called 'man of arc'.

and actually....

think of the radius as a cone from 0 degrees to 45 degrees. the farther away from the center/point of the radius to the diameter of the arc the farther apart the point of minutes becomes. (=1 inch @ 100 yds & 3 inches @ 300 yds).

the radius is the distance from the center point of the arc (end of barrel) to the arc (target). The "cone" (angle) always stays the same where 1 MOA is 1/60 of a degree, but gets wider in curvelinear distance (not degrees) as the radius increases.. Diameter (2r) has nothing to do with it. Just had to throw that out there cuz dude, ya screwed that one all up, heh heh!

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MOA club member

MOA is 3/4 of a MOAN. It is used when the situation doesn't call for a full MOAN. For example, if somebody stepped on your foot, you'd exclaim "MOA". If on the other hand, somebody runs over your foot with a car, you'd exclaim "MOAN".

Moral of the story... Don't stand so close to moving vehicles.

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Minute Of Angle. 1/60 of a degree. It is approxamitly 1" per 100yd (actualy it's 1.037"/100yd), so 1/2" @ 50yd and 6" @ 600yd are both 1MOA.
Groups are measured from center to center of the 2 furthest holes (outside to outside minus 1 bullet diameter is the same thing) and than converted to MOA

Yes the 1/60th of a degree. Origins on a wooden hull in the ocean somewhere on a flat earth with dragons!

Then there is what it means to a lot of folks and that is this: The spread of the three closest shot holes out of a 5 or 10 or 20 shot group, or out of a large number of different three shot groups.