I have a Charles Daly 20 ga superior grade from about 1969 that is skeet/ skeet in beautiful condition. It does take 2 3/4" and 3".
Couldn't use for water fowl, steel shot would be bad for it.
For sale - one CZ Supreme Field shotgun, 28 gauge with 28" barrels and factory screw-ins. Only modification is the addition of a Kick-Ez pad that had a professional install (original plate included). The shotgun has a few minor handling marks but has very few shells thru it. I would consider it...
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Check out BRILEY thin wall choke tubes fo older S/S or O/U's with out choke tubes. They did one for me 30+ years back.
you will be able to shoot some steel shot through them up to a certain size.