Seems the 3 MOA thing is based on peoples' experiences.
I haven't had a chance to shoot 50 or 100 yd groups with mine. They were acquired after this winters' lousy weather started...
My 15-22s (I have 2) will shoot 5 shot 1/4" groups at 50 ft. Now let's get straight what that commonly means:
A five shot 1/4" group will have a GREATEST CENTER TO CENTER distance beteen any two of the five rds of 1/4". In the case of 22LR that would put all the holes COMPLETELY INSIDE a 1/2" diameter circle.
I've also seen people shoot 10 shot groups, pick the 3 that are closest together and use those as their 3 shot group accuracy. Great for bragging rights I guess, but for anything else, just nonsense...
If the requirement is that any two holes have to be within 1/4 inch CTC, how can the diameter of the circle be as large as 1/2"?
Example hole #1 is the dead center of your 1/2" diameter circle. Hole #2 is 1/4" away from hole #1 at the 9 o'clock position. Hole #3 is at the 3 o'clock position and is 1/4" away from hole #1.
Holes #2 and #3 don't meet the test of GREATEST CENTER TO CENTER distance beteen any two of the five rds of 1/4".
They are 1/2" away from each other. To me, that makes the group a 1/2" group.