Interesting experiemnt I just did, with my Pro Chrono. I've been reloading for the past 28 years, and have never NOT weighed a charge on my scale. Never. For the past 20 years I've been using Redding BR power measures, and have watched guys at the range and at matches just set their measure and start charging cases(I used to shudder). Now I know, all you progressive reloaders just set it and start throwing charges too but I never have. Hell, I just got a tumbler a few years ago...I'm old fashioned and dont deviate from what works lol. Anyway, I decided to set my measure, throw a few test charges and then proceed to charge 10 .44 magum cases with a target load I use very often, consisting of HP-38. I set up my Chrono outside and shot all 10 round through it just to see what SD would be without weighing and trickling to perfection. 10 shots gave me an SD of 11! Hows that for uniformity. I still lan to weigh every rifle charge, but all my handgun loads will be thrown without weighing every one....maybe weighing every 15th or so. Sure speeds up my replenishment of handgun cartridges, and without a Chrono I would have never tried that. Again, big step for me...I/m cautious and a creature of habit