Blaster, Glad to help out when we can. What you have there is not only a powder cartridge loading tool, so you don't have to put your fingesr down the barrel to align the aluminum foil cartridge with the chamber, but also it is a tool which will form the cartridge "cup", itself, then, after a twist of the aluminum foil tail, you use it again for forming the muzzle end of the cartridge. We have a set of these tools that we machined from brass and they look very, very similar to yours. As long as you don't go and WHACK the loading plunger with a mallet to seat the charge, we can't see any more danger than placing it there with your fingers. Finger tip pressure should load a perfectly aligned charge into the chamber without any difficulty.
Good looking mortar too!
Tracy and Mike