If you would only buy PW's. I'm gonna fess up here. I've got a Mec that I make 3" shells on. (Just because I'm to cheap to buy the tooling for 3 inch on my PW).
Called the good folks at Mec Probably a good generation ago on this very problem. Their solution for this was a 14" dowel rod and on the upstroke to tap the shot tube. Pretty low tech but it works.