In building up loads for accuracy, what reductions have you seen just in changing powder charge alone? Type of gun and at what distance? Size of groups is good.
With me it seems that biorhythms are the main factor. I can have a great day at the then next time I go I look like a novice and next time I'm Jerry Miculek again. So I'm not the best judge of variables outside of myself.
PS I took some movies today of dry firing a J frame, an L frame, a Shield and a DAO 3rd gen. I took some from the side, and I took some into the camera lens for a head on shot. Out of about 20 shots, 2 moved slightly. The others were rock solid.
I should take time to go to the outdoor range with a sandbag.
Of course I was fresh, just had to set up the camera and shoot at it. Not carrying and unpacking stuff in a noisy range and trying to shoot. Usually, it takes a few shots to warm up at the range. So when I'm being assaulted, I can say, "How about give me a few warm up shots."