Depends on how far apart they are set.
1 MOA approx equals 1" at 100 yards.
that means .010 inches (one one hundredth of an inch) approx equals 1 MOA at 1 yard.
We will assume that your rings are space 6" apart, which is 1/6 of a yard. So a .010" offset will mean a difference of approx 6 MOA. If your rings are 5" apart then the difference is about 7 MOA. The math is 1 MOA divided by the fraction of the yard distance (which is the same as multiplied by the inverse). 1 divided by 1/6 equals 6, (6" equals 1/6 of a yard, 5" approx equals 1/7.2 of a yard)
Simple math, it could be wrong but I hope it helps. If you use two inserts (one in each ring) double the MOA gained. Just remember to put the rear insert thick on the bottom, and the front insert thick on the top.
Last edited by Jimro; March 16, 2009 at 02:43 PM.
Reason: unsure of my trig...