12 gauge Remington 870 or Winchester 1300, with a good butt pad, and light load birdshot.

1100LT 20

A great starter shotgun when I was 14 and still a a joy 25 years later.

FH: I know you are looking for an autoloader, so forgive me if this isn't helpful, but I purchased a Benelli Supernova 12ga pump and the recoil is almost nonexistent. And, I'm not such a big guy that mass is the difference.

The Supernova's stock is designed to mitigate the recoil and it works very well. One can find one for about $450 or so.

Anyway, worth looking at. It's a real soft shooter.

This is definitely dead horse beating, but since this thread won't die:

Fixed breech guns (including pumps) have more felt recoil than autos, given similar loads and similar gun weights. Gas autos will feel softer than inertial or recoil autos. (The Supernova has some sexy recoil mitigating stock features, and I have never shot one, so maybe it is the cat's meow - I don't know.)

I have lots of shotguns - too many. But I have 12 and 20 gauge pumps and autos, and without exception the autos feel softer than the pumps. I love 870s, and I love my Winchester 1300, and I really love an old Ithaca pump, but they all recoil more with similar loads than do their auto conterparts. Even the Auto 5 I have, which is one of the least soft shooting autos, is softer shooting than any pump I have. I really love O/Us, but they recoil more than autos. For me, the O/U's handling qualities outweigh the recoil penalty, but there is no doubt they hit the shooter harder.

If felt recoil is a concern, get an auto. Get a gas auto over a recoil operated auto. That means an 1100, an 11-87, a Beretta, a Browning Gold, a Winchester X2 - there are lots of them. The OP is concerned about recoil and all the suggestions for pump guns (with the exception of the higher tech Supernova) just ignore that reality.