Your topic intrigues me because I am currently working on a swivel breech project , myself. I have been building guns for many years, but this is my first attempt at this type of gun. My breech mechanism, lock and buttstock are complete and I am beginning to forge my barrels. This glimpse at your work has kind of stopped me in my tracks. First of all, I'm impressed at your inletting prowess. That is some fine looking work. Secondly, Is this how the forestocks were , typically, constructed? I tend to just proceed with building without doing real thourough research. You might say that I just figure it out as I go along. It was my intention to build, bore and rifle two straight barrels and join them together with dovetail keys and/or solder. I, then, planned to grind and file the swamped profile into the barrels, now joined as one and use a two slab forestock, screwed onto either side.The forestock assembly would be semi permenently affixed to the forward swivel plate. Your construction method provides the obvious benefit of having individually removable barrels but I wonder about the strength of the system should it be dropped or recieve any rough treatment.