My characters have access to a small cache of .45 ACP ammunition (but no weapons to use it in) and instructions on how to build a British Sten 9mm submachine gun (but no 9mm ammo). I found this thread on a firearms forum about modifying the Sten's magazine to accept .45 cartridges, but that would be for using the Sten magazines in a firearm that is already chambered in .45, not a Sten itself. What changes would have to be made to the Sten, which is chambered for 9x19mm Parabellum, to allow it to fire .45 ACP? Or might changes need to be made to the ammo - some powder removed from the cartridge, maybe? IDK. If anyone knows anything about this kind of stuff I could really use the help.