Here is a photo of a Webley with and extend rib third fastener system very similar to my shotgun:
That could well be a W&S Model 400, made in different grades from 1900-46, and replaced by the 700. Earlier Scotts, at least from the photos in the Scott book, used either a doll's head extension or, more commonly, one with a piercing for a square crossbolt in the extension. The later ones, if they had a rib extension, used the type shown in the photo or the standard Greener with a round piercing in the extension. There aren't any photos in the Scott book showing a fork-like extension (metal above and below the bite) similar to the one on your gun. Or at least I think that's your gun. I've gotten somewhat turned around in this very long discussion. Might be that someone here is aware of a W&S with a rib extension like yours, however.
