No clue. The stocks are beat, but man, that's a cool-looking old gun! Loaded with personality. Kinda looks European to me, maybe even South American. Definitely a keeper, I hope you find out some info and share it with us.
I think its a belgium proofed, french built LeFecheux 11mm pinfire. One thing is certain...pachmeyer dont make grips for it!!!!!..Cool gun..like all old guns. Enjoy and let me know if i was right..just off the top of my head, no books were consulted because im at work