Repeating Vacuum Bazookas

The vacuum bazooka is a classic demonstration, you attach a vacuum cleaner to the side of one end of a pipe, cover the end with a piece of card and then drop a projectile down the other end and a the projectile flies down the tube and out the other end.

I got a bit carried away and worked out various ways of building repeating vacuum bazookas, because it sounded like fun (and because I could).

The Vacuum Revolver