How to measure a shot group: August 8, 2008

Measure a group by measuring the distance from the far edges of the two widest shots, and then subtract one bullet diameter to get the distance between the centers. If the two widest shots of a group of .22-caliber shots measures 1.220″ across their widest distance, the c-t-c distance is 1.0″. The math is simple, and it works the same for all groups and all calibers… Dirt E. Harry