You’re cheating yourself on results. You are measuring your groups “end to end”. The correct way is to measure “center to center”.
That is to say, measure from an outside shot’s center of pellet impact to the furthermost pellets center of impact. That gives you a much closer group, and accurately indicates where the pellets impacted dead center when it hit.
Still, pretty good shooting for a guy with one glass eye…did you have it ground to prescription???
😀