I've only had issues with the usual suspects like Unique and Varget.
Large flaky powders having static issues people either use dryer sheets of ground the press.
Charge inconsistency check your failsafe rod adjustment. Handle all the way forward top of failsafe rod should be at the bottom of the slot in the bellcrank with partial compression of the failsafe rod spring. Check the tension on the bellcrank screw. I've received powder measures where this was too tight and the powder bar didn't move freely.
Already mentioned but slow down, pause at the top and give it a good three count, and try to do each stroke with the same force and speed.