I'll get some pics of the jig this weekend. It's just a 2X4 that I put a 5/8"(I think it's 5/8") hole in sideways and trimmed down on the table saw until just the edge of the shell sticks out. Put it on a wood surface, put a shell in, cut with a large knife, once you are through the shell's crimp make sure you hold the knife next to the shell's hull or the shot will pour out and make a mess. I dump the shot while the shell is still in the jig.
It's really some thing that you could do with out pics as it's just a hole in a board Good luck!