Unless you using ball type powder's,none of the powder drop style dispenser's will be right on each charge. Extruded type powder's don't fall uniformly into the dispensing chamber,so each drop weight will be different. That's just the way they work.

I also gave up on the electronic powder dispenser's,I've tried RCBS,Lyman,Hornady,and Smart brands. They all over/under throw charges,yet the scale will show the weight that you programmed into it. It always took me more time to load my precision loads with an electronic dispenser,than it did doing it by had with a manual powder drop,and trickle in the last few kernel's of powder into the pan on my beam scale.

There is one electronic powder dispenser that works,but it cost around $1k for the A&D FX-120i scale and Autotrickler V3 unit. I can load a lot of cartridges by hand for $1k.