Originally Posted by Doc Hoy
I am fairly careful with measuring the charge as I use that contraption I came up with last year so I may not know the exact weight of the charge but I know that all charges are very similar in volume. I think I am getting very close to the indicated charge plus or minus one grain. I mold my own round balls and can get standard deviation in diameter down to less than .001. I think I am at least moderately successful at reducing variation in the factors contributing to the formula. Yet if SD is as I have observed, I get as much variance from shot to shot because of unidentified factors than I would if I randomly chose a different powder. Both factors equal about 95% to 105%
You might try chronographing five shots loading the same chamber every time. A lot of people who shoot NMLRA revolver matches mark the most accurate chamber in the revolver and use it for every shot on the slow fire targets.