Bang your powder measure lever.
Bang the lever twice on the up stroke and maybe to empty it also.
If powder "bridges", then what's left of the bridge goes into the next case with another load. This could cause an overload. I'd be certain this didn't happen to you.
I'm not familiar with your RCBS Charge Master digital scale, so excuse me if I'm missing something.
Does a primer have enough power to cycle the pistol eject a case???
Bang the lever twice on the up stroke and maybe to empty it also.