I recently sent my vintage Francotte SxS I n to a Master Gunsmith for a cleaning and to have forearm tightened.

My other request was for any information regarding the date of manufacturer (1900). Are there any sources available for proof marks prior to 1922? The proof Mark is U with a star over it (1923 & 1953). There are no importer marks. The shotgun has a cheek piece, a feature I haven't seen on other Francotte shotguns.

Any suggestions are appreciated.