Thank you Birdhunter, I was thinking of using the actual bottom plate & lumps off the shotgun barrels by milling them off, I have seen how they are fitted with slight recessing into the barrel bottoms, making up a shoe lump from scratch is way out of my skill set, really a barrel set build is to !

To me only the .577 or 12bore rifle are worth building on a 12Ga shotgun frame .

I still have a C&H 8 bore action & 2 new barrels waiting to be put together, only been with the gunsmith for 5yrs !