Clark, I measure with digital calipers to the outside of the group, then subtract the diameter of the bullet to get center to center of group. I try to get the edges as close as possible and not do any cheating to make it look better. If you measure outside of holes you are not getting the true center impact of the bullets, that's why you subtract the diameter.


If I agreed with you, we'd both be wrong.

Bluetick serpentines around green fields and rock spit a lease