I load 2.5" 20-gauge, 2 9/16" 16-gauge, and 2 5/8" 12-gauge shells. I use the homemade shell cutter illustrated in Chukarman's earlier post, but I added a large-headed wood screw to the end that goes in the hull so that I can adjust the depth of the cut. Back up the wood screw with a few washers to help keep it from "re-adjusting" itself when you're not looking.
Look in a shotshell reloading manual for loads with lighter shot charges with fast burning powders like Bullseye or 700-X. Some of these loads will require placing one or two nitro cards in the shot cup. Omit the nitro cards and you've largely compensated for the shorter hull.
