I use 2 1/2' (or 65mm) shells. RST and Kent Gamebore make good ones. Also, visit The 16ga Society website for further choices. As a point of interest, one of our members shot quite a few boxes of local "Stopping Power" ammunition 1 oz #5 2 3/4" in his #1 frame DHE Parker with no ill effects...other than on the ducks...
