I've bulged a few chokes on a very similar choke system. Remingtons probore. Threads up top and a very thin section down bellow. A carlsons mod with 3 inch challenger bb and a patternmaster code black goose with 3 inch challenger bbb. Crazy thing is I dont shoot much challenger yet thats what did it both times, but I dont see how I can blame challenger. Both were replaced by the manufacturer. Carlsons was replaced with a stronger steel version he just started using this stronger steel for these "weaker" choke designs. Both manufacturers said no bigger than bb through the chokes.
My favorite goose load is 3 inch 1.25 ounce federal speed shock in bb or bbb. With an imp cylender choke it patterns better than all other loads with a modified choke. Should be a win win, less choke stress and better patterns. Cant always find it though. Still shoot lots though a mod choke or the patternmaster depending on load. I would not shoot bbb or t shot through anything tighter than a imp cylender.
I have an older patternmaster in a 870 that is getting pretty tight as well but nothing like the 2 pro bore chokes did. It still patterns well so we keep shooting it but one of these days it will get sent back as well.
Always pattern the gun, some bore systems/guns dont need to be chokes like crazy with some shells. Federal speed shock in bigger sizes almost always shows this trait. I recently patterned my sx3 with some goose loads and with score 2.75 bb loads it patterned good with the imp cylender and then got WORSE as I tried tighter chokes. Winchester x pert patterns got better with the mod than the looser choke. Federal blue box did better with the imp cyl than the other loads with any choke, and just got tighter with the mod.