I hear that using a cling free dryer sheet run through the tube will help for static for the powder. I have used that for handgun on the funnels etc so powder doesn't stick. As far as Kevin's idea about static, I saw a forum somewhere once where the poster used a vinyl record anti static gun to zap his tube periodically which kept the powder dropping. Seems an expensive fix, but if you have one laying around or see one a flea market it's an idea
https://www.walmart.com/ip/Milty-Zer...6&gclsrc=3p.ds