It's a pretty easy trick to trim the old crimp off fired hulls with the BPI Trim Doctor II. I have new 3" hulls and did cut one down as a test but I don't want to waste the new 3"ers just to fit my load. I don't have any 20ga. 3" once fired on hand. Cutting 2 3/4" down to 2 1/2 or smaller is an option. Gp