No need to buy special 16 gauge rounds.My uncle had a drilling in the short 16 ga. He simply used a bottom drill bit(no taper,don't know the specific size) to cut the center out of the crimp,so the shell once fired would not be longer than the chamber. Then he would seal the end of the shell with wax or hot glue. Worked well for him. Just a "poor boys" answer to a problem! memtb