I'm putting my money on Monty. I have seen several Westleys bar in wood guns that had the same look yet were never pinfire. My friend owned one for several years and we examined it quite closely under magnification. Another friend owned a very early Westley 8 bore rifle that also had this style fences and hammers. I had that one apart to build a new toplever spring and again there was zero evidence of a conversion. I think it was a stylistic feature that Westley Richards felt went nicely with the bar in wood action. Just my opinion, I could be mistaken.

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