I haven't patterned my shotguns in years. The last time I did it was when lead was still legal for waterfowl, back in the 1970s. In those days I used the Remington Nitro Mag 2 3/4" "short magnum load" that threw 1 1/2 oz buffered no. 4 shot. This was a lethal reaper of waterfowl out to 60 yards if you could hit them that far.
Obviously the modern stuff isn't up to that so I got some 30" circle patterning targets with a life size picture of a mallard in the middle. I took my L.C. Smith and my 870. I tried a 1 1/4 oz bismuth load in my L.C. Smith first. Since the old gun was made in 1926 for the paper shells of the period I knew it patterned tighter with modern shells so I set the target at 50 yards instead of the usual 40. Both the full and modified barrels shot what amounted to full choke patterns five hits are supposed to be required to guarantee at least a couple of killing hits. The full choke barrel delivered six hits and the modified barrel five so out at 50 yards I should be good, and I never shoot that far anyhow. Steel groups very tight and for that reason a lot of folks use modified barrels when shooting steel for waterfowl. I reset the targets at 40 yards put a 1 1/4 oz load of steel 2s downrange through the full choke barrel of my 870, The result was 9 hits (very dead duck.) For grins I shot another 1 1/4 oz steel load at forty yards through my improved cylinder choke on the 870. Not satisfactory at 40 yards. Four hits and holes in the pattern that would have resulted in either an un hit bird or a non retrievable cripple.
Interestingly some of the steel pellets penetrated the 1/4 inch plywood back I use for my targets. Encouraging. Steel has come a long way. In the past 10 years I've killed ducks dead with steel at distances I know I would have been chasing them if I knocked them down.
One thing, the duck on the target is quartering in on final from left to right. My patterns were off a bit to the right, seems I can't get over leading that duck even if its still, LOL.