I know the 31 is a full size 357 and the 22 is a full size 40. Is the barrel the only difference? Im wondering if there is a difference in the recoil springs or outside diameter of the barrel.\n\nWhat I really want is a 357 glock with a longer barrel. Maybe even 2 or 3 inches. Im wondering if they even make such a barrel and if it would be easier to find it for a G31 or a 357 converted G22.