Can you post some photos?
This one sounds like a LOT of fun to figure out!
Personally, I have never come across anything even remotely resembling what you are talking about.
Webley did make 2 sizes of frame, big ones for the .455/476 and a small frame for the .22, .32 and .38 models. How a small cylinder became mated with a large frame is beyond my imagination.
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