I think it is a early french action. I have seen an old shotgun of same type at a gunshow, it was very pretty. I would be worried about what would happen if the breech failed. It's not a problem for the french, they shoot from behind cover with the firearm held high over their head with face tured away. If the breech were to fail, it would be a good reason to run from the action, and to search for it back at home!!!

JD