View Full Version : Need Explanation of MOA for Optics

January 25, 2002, 10:56 AM
I am fairly new to the shooting sports and am considering putting a scope or possibly an Aimpoint on my Ruger MK2 (KMK678GC). I picked up one of Clark Customs excellent Weaver scope bases to replace the Ruger propriatory one, and on researching optic devices the term MOA is referenced but I have yet to find an explanation on what it means. It seems critical, as the various scopes use this for quality comparisons.

January 25, 2002, 11:06 AM
One minute of angle is one sixtieth of a degree of angle.
One minute is about one inch at 100 yards.
One minute dot covers an inch at 100 yds.
One minute about ten inches at 1,000 yds.

Just a measurement of angle.


January 25, 2002, 11:07 AM
MOA is Minute of Angle. It is roughly 1" at 100 yds, 2" at 200 yds, etc. So a gun with MOA of 1 would shoot groups of 1" at 100 yds. A 1/2 MOA is groups of 1/2" at 100 yds.

In regards to scopes, it is how much clicks on the scope move the point of impact. A scope with 1/4" MOA will move it's point of impact 1/4" at 100 yds. 4 clicks would move it 1".

January 25, 2002, 12:19 PM
Thanks guys, that information was very helpful. So if I had a scope with a MOA of ½, at 100 yds. I could adjust in ½" increments...¼" at 50 yds., etc. This info definately is leading me away from Red-Dot scopes with a MOA of 4 !!

January 25, 2002, 01:22 PM
This info definately is leading me away from Red-Dot scopes with a MOA of 4 !!
Well, they are used for different purposes. If you want to shoot a half-inch hole in paper at 100 yards, then you definitely need a good scope. If you want to be able to hit a target in the center of a rubber tire rolling down a hill, the Aimpoint is probably a better choice. One's more precise, the other is faster to pick up moving targets. Both have their place, depending upon your needs.


January 26, 2002, 12:34 PM
This info definately is leading me away from Red-Dot scopes with a MOA of 4 !!

You may be confusing the size of the dot with the resolution on the adjustment dials.

MOA is just a term used to represent an angle that subtends 1/60th of a degree.

My Aimpoint Comp ML features a 3 MOA dot. That means the dot appears to be 3" in diameter at 100 yards.

My Comp ML also features 1/2 MOA windage and elevation dials. They are set to change the point of impact 1/2" per 100 yards distance per 'click'.