bob, if you are not recoil tolerant, do NOT buy a 20 gauge. You trade reduced payload for a lighter weight gun. The recoil stays the same.

To compare the recoil from an auto 12 to a pump 20, I can tell you that my wife will shoot two rounds (115 shots or so) of sporting clays with her 391 gold, and go home comfortable and happy. When she shot her pump, she asked "how many more" halfway through the first round.

Another comparison: my 12 ga. BPS pump with 1 1/8th handicap target loads kicks about the same amount as my Browning Gold with extra heavy 1 1/2 oz field loads. The recoil reduction of a gas operated auto is substantial. The recoil operated autos work great, but they do not give you a rebate on the recoil like the gas guns.

HTH, Dutch.

Now we're down to the licklog. You mostly want to shoot grouse and clays, for which a 20 o/u would be perfect.

But would it do in a turkey? Well, sure, if you get it in close enough. The difference in a 12 gauge and a 20 gauge as far as turkeys are concerned is one of range: With an ounce and a half of shot, you'll get the same amount of shot at a greater distance into the turkey's head and neck than with an ounce and an eighth. But remember, at a greater distance, the shot will be traveling slower, so in real world terms, the 12 gauge is good for about 15 to 25 feet more range than the 20. If you can live with that limitation, then go for the 20 and you'll enjoy your grouse and clays shooting much more than with a twelve.

But as I said before, you ain't gonna shoot a turkey on the wing flushing out of a woodpile like a quail. A turkey is a ground dweller and feeder and walks about most of the time just like the deer and elk he shares the habitate with. I find it infinately more satisfying to pick one off with a .22 Hornet or a .222 loaded with FMJ's than plastering one with a load of shot. If hunting turkeys with a rifle is legal in your locale, then give that a try instead of a shotgun.

I just bought my son a beretta OU for Christmas. I forget the model name but it is a blue- wood stocked - 12 ga field gun. It has 28 in barrels with screw in chokes. At Gander Mtn it was about $1200. He has already used it for waterfowl and upland birds and loves it.
The most inportant issue is how does the gun fit you. You are mounting and shooting a shotgun rather than taking the time to settle and aim a rifle. The gun must come to your shoulder smoothly and be on target when it gets there. If you have to adjust to it, it doesn't fit you. I'd suggest that you go to a gun shop and try shouldering a few different guns. You will quickly discover what you prefer. Personaly, I find a double, especially a side by side, fits me the best.
Also, Savage is introducing the Stevens 411. This is a Russian made SxS with choke tubes for about $400. There was a story about it in the NRA magazine Rifleman. The gist of the story is that it is a worthy succesor to the old Stevens 311 which they called the traditional "workingman's double". I took my first bird with a 311, if the 411 is as good it could go just fine.