Paul~
I know all about the conventional advice for shooting steel, but, like Capt Jack, I use a full choke (my 1925 Winchester Model 12, 12 gauge) as my everyday gun - or my Dad's Winchester Model 50 - also a full choke 12 gauge. I use Kent Fasteel BBs (2 3/4") for Canadas. I fondly recall many long/tall shots with that combination. We patterned our duck and goose loads earlier this summer and found what I expected: I pay a small price on "in-my-lap sucker shots" by being a bit too tight - but enjoy a nice dense 30" pattern at 40 yards. If I'm trying to hit incoming Woodies in the Hemlock swamp, I use my 20 gauge SxS with IC in both bores - but otherwise I am quite content with the full choke.
All the best,
SJS