Burris says "30 mm rings come with two sets of "0" (zero) inserts and two sets of +10 and –10 (equal to +/– .010”). These are the only insert sizes available."
where did you get the ±20 from?
Burris says "30 mm rings come with two sets of "0" (zero) inserts and two sets of +10 and –10 (equal to +/– .010”). These are the only insert sizes available."
where did you get the ±20 from?
Something to consider - the Burris offset bushings provide controlled alteration of the scope's alignment. The numbers on the bushings are thousandths of an inch.
The effect, in minutes of angle, is going to vary according to the spacing of the rings.