These percussion inserts go back pretty far! I have been acquiring all the Lefaucheux ads I can find and one of them mentions:

[Linked Image from photos.smugmug.com]
PERFECTIONNEMENT.
FUSILS LEFAUCHEUX, 10, rue de la Bourse.
MM. les CHASSEURS sont prévenus que dorénavant les FUSILS LEFAUCHEUX pourraient, à défaut de cartouches, se charger à la baguette comme les fusils à piston, an mayen d’un CULOT DE NOUVELLE INVENTION que maison Lefaucheux délivrera gratis avec chaque arme sortant de ses magasins.
On trouve dans la MAISON LEFAUCHEUX un assortiment complet de toute espèce d’armes à feu à charger par derrière ou ordinaires à piston.

This advertisement is from the August 15, 1842 issue of the Journal Des Débats. Here Jubé (guy who owned Lefaucheux's company from December 17, 1835 until January 1, 1845 ) advertises an improvement. He mentions to hunters that they no longer need to worry about running out of pinfire cartridges as he will provide a new invention of a reusable cartridge that can be loaded with percussion caps free with every gun purchase.

The Westley Richards one however looks like it was never a pinfire and could never be a pinfire unless there were some additional kind of insert. I had a pistol that could take similar cartridges or an insert would screw in to allow a pin to be held in the giant square hole.
[Linked Image from photos.smugmug.com]

But guns were definitely made that only worked with these adapters. Even Eugene Lefaucheux made a revolver as such which I once owned:
[Linked Image from photos.smugmug.com]
The hammer itself is even a bit hollow and there is no way it would work with regular pinfire cartridges. He even advertised it as so (You can see the ad here: https://casimirlefaucheux.com/t/revolver-marked-lefaucheux-fils-next-to-come/176 )

And here's a little more history on other percussion adapter cartridges in this little article I wrote some years ago:
[Linked Image from photos.smugmug.com]

Last edited by AaronN; 06/21/21 09:54 PM.

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