excellent point George, and right on, for the most part.
I use a lyman55 and it can be finicky to set up. but I found a fast way to do it.. Hand weigh a correct charge, open the dump all the way and pour the charge in so it goes all into the barrel. then just close it up until it pushes the powder charge almost til its falling back out over the top of the charge barrel. Then lock it down and fill it up with powder. usually the charges thrown at that point are within a couple tenths and can be brought into zero with just 2 or 3 adjustments.