Smitty,
I've done it twice, both times with old Stevens 311s. The first I did about 25 years ago, cut the barrels to 21", added a Williams short ramp front and one of their adjustable rear sights and was able to get 4-5 inch groups at 40 yards using cheap Remington green box slugs. The current one I've cut to 22" and gave it the same sights. I had a welder tig a wedge between the barrels at the cut just to keep them solid. I'm handloading my slugs using a Lee 1 Oz mould, Double A hulls and Bluedot powder. The load development is not complete but it looks like I can match the earlier results at about 1300 fps. Both got whatever recoil pads were handy and both need/needed trigger work, triggers are heavy and rough, OK for a cheap shot gun but not for trying to shoot groups. I've not tried buckshot in the current but I'd expect typical cylinder bore results. Both turned out to be stout, good looking guns.