1 MOA is about 1" at 100 yards(atually 1.047 I think). Or I should say 1" per 100 yards.
1 MOA at 100 is 1"
1 MOA at 200 is 2"
1 MOA at 300 is 3"
1 MOA at 1,000 is 10"
So when you talk in MOA the size depands on the range. A .5 MOA group at 100 yards is 1/2"
A .5 MOA group at 600...