After having used ACB's for years on four different machines, I can truthfully say " they have never changed drops on their own". There is a allen head set screw to lock them where they're set. I'm not really sure what " stable and strong " means when it comes to charge bars, but I just took one out and couldn't break it with my hands. Couldn't wiggle the adjustable part, so it still must be stable. There are some who like them, and some who don't. The Lee press is ok, just not as versatile as a Mec. If you look in a manual from one of the powder companies you'll find there's usually a 3 or 4 grain spread for a load. Pick a low one and you'll still be safe even if by chance you dump a extra grain or so in the shell. Mec bushings are rated for the single stage press and the drop will be lighter with a progressive press. Shotgun reloading isn't metallic reloading. Two or three tenths of a grain powder either way won't make any difference when loading a shotgun shell.
