You got lucky! Sometimes things don’t pan out! A 7 1/2lb 28ga probably put everyone off. But now you got a lightweight British 12! I would have those cones double checked, does Briley make tubes for 2 1/2 chambers?
Apparently they do. They were installed when I recieved the gun, but I checked them with a Brownells 12 ga chamber gauge and they are exactly 2-1/2 inches, so haven't been lengthened. Wall thickness is more than adequate through the forcing cone and beyond. I've done all my own gunsmithing work for 30 years, have a complete machine shop and all the measuring tools needed for shotguns and rifles, so I have completely checked out the barrels, including a good bore scoping.
