The only powders I have trouble with in my RCBS Uniflow are the IMR "stick" powders because they feel like I'm having to "cut" some of the sticks to get the cylinder to move.

Years ago, I used the powder measure on my Lee Load All shotshell loader to dispense powder for .223 Remington. Since it was all gravity driven, it worked great until the abrasion of the sticks wore enough of the bushing away to start to interfere with the loads.