Quote Originally Posted by slow_runner View Post
I would venture that it is a hybrid. That barrel appears to be a (later?) replacement; the blueing condition is markedly different between the barrel and cylinder, cocking arm and trigger block.
Dunno........The proportions and bits all look correct for a BSA barrel of the original type, especially if you click on them as they come up quite big, then compare to other examples say on danny's site.......except for possibly a replacement rear sight insert. It is also quite common to get an original prewar gun with differences in bluing due to handling, ie. the compression chambers often have more patina than the barrel due to just more contact with skin, and photos are notoriously inaccurate to go by.

Just my thoughts, will be interesting to find out.

ATB, Ed