CharlieNC
Gold $$ Contributor
I would like to point out one thing here. Targets see ES. and that is the only number that concerns me be it velocities or charge weights. Generally sample sizes are too small for SD to have much validity, but because chronographs include that in their readouts they are referred to in shooting related posts, articles and videos all the time. I think that this has obscured rather than clarified results. When I read your post, the first thing that came to mind, after being glad that you had shared the information, was to wonder what your ES had been.
When I test a scale weighing the same object, if I have one weighing that extends the spread, I do not throw that out because I would not know that it had happened if I was weighing a series of objects or charges. Similarly it will be the extremes of velocity that would probably be my most divergent shots in a group shot at long range. There is no provision for scoring the SD of bullet impacts. Thank you for posting. I hope that my response has not offended you.
Boyd
Of course the target reflects the SD with every individual shot, the ES just happens to be the worst case. Unless something is not "normal" (pun intended) the groups will generally be 4xSD. And with limited data the SD is a better predictor of what to expect in this regard. Now the ES of the shots will be of more concern to a group shooter, but for score they all matter. Fclass scoring rings are a very good reflection of SD as shots pile up more in the center (average) and the number of shots trails off at the further rings; stacking up like the normal bell curve.