It is essentially the same as the Webley-Fosbery, but arranged differently. It works on the same "upper assembly recoils on rails, working the cylinder and cocking the hammer" principle, but the system for indexing the cylinder is a hand working on gearteeth at the back (like in a conventional revolver) rather than in big zigzag grooves on the sides. That's also why it doesn't need to recoil as far, because the advancing action is all happening at the back of the cylinder rather than needing to involve slots running the full length of it.

The W-F wasn't the only revolver to have those zigzag grooves; early Mauser revolvers, for instance, had a similar cylinder-advance system. It was just another way of setting up a mechanism to do that job. It's a simpler, easier-to-build mechanism—I've heard of at least one design for a 3D-printed revolver using a zigzag system—and some designers considered it more positive because it involved bigger parts, while others—and history, it seems—concluded that they were too much more susceptible to getting fouled with debris and jamming the works.

--G.
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Benjamin D. Hutchins, Co-Founder, Editor-in-Chief, & Forum Mod
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