Dumb Question, how about taking a fired 3 or 3.5" 12 gauge shell, just barely trimming off the crimp, resizing and priming the shell, putting it into you 12 Gauge, adding black powder or BP substitute, add overwad, shot and another overwad, presto, a 12 Gauge ML. Not legal in ML only areas because it is still a firearm, but, would it work???