I have Winfer and was aware of that - and it is documented that Westley made Martinis FOR Francotte. What Winfer describes would work with single shots. However, there is no reason to believe this was ever applied to doubles, because the manufacturing process was so different.

There is also the matter of completeness. Many British double rifles have barrels made up from blanks supplied by Krupp, but that doesn't make the rifles German made. A rifle made up in England from barrel blanks and an action forging supplied by a vendor in Liege is not Belgian made. "Belgian made" implies a gun that was mostly completed in Belgium. I've never seen any evidence to support the contention that any British makers routinely put their own name on double rifles made primarily in Belgium.
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