Thank you for the information, now I aint quite so dumb!!!!
I have a French 16 ga. that has shoe lumps and it was tripple proofed so it should take the pressure of a rifle conversion. As a matter of fact it is the highest pressure proofed gun I have so I would not say this would be a weak way of building barrels. The lumps on this gun are silver brazed or somthing simular, into place it is not a lead based soldered. For that matter the ribs and barrels are soldered togther using the same stuff! The gun was made by J-B Brunet A' Chartress do any of you know any thing about this maker?