To get an extra shot! I used to be a ruger No. 1 shooter (cheap big bore guns) but, I was nervous using one against DG. Hence, my life long lust for a double now had a practical reason for being. As I said before, I have two guns: my Merkel 375H&H SxS and a Berreta 20Ga O/U. What more is needed, except a set of 470 barrels