Sounds like a Belgian-made pre-WW2 Browning Auto-5 shotgun, although you did not specify the model of shotgun. If so, it was produced in 1931. Does it have a sliding safety that goes front-back through the trigger guard or a cross-bolt safety?
As the barrel inscription says, it is designed to fire the 2-9/16" 16 ga shotgun shells popular until WW2, not the now-standard 2-3/4" shells. Do not try to fire it with 2-3/4" shells, it will overpressure and it will jam when the hull becomes stuck in the ejection port.
It can be modified by a good gunsmith to fire the longer shells, but the job will cost as much as buying another shotgun of similar type.