FWIW, this is a link to a pretty good blog by a gent that is a professor of veterinary medicine at Viginia Tech. On the green bar at left, scroll ALL the way down until you come to an article called "The Minimum Battery". You COULD do a lot worse than following the outline he gives.
THE NEW RIVER VALLEY OUTDOORSMAN
I would have a hard time deciding which 10 of my children I would keep, and which I would orphan! Yes, the 12 g is a must, but the 20 makes such as good dove gun, and the 410 is really fun for quail, and that 16 was such a bargain.........
