There is a lot known about Pieper and his Bayard trade marked guns. If you can read French, there is an excellent book about Pieper.
If you take the barrels off, you will find the Belgian proof marks. You can look them up here:
http://damascus-barrels.com/bp.html
Pieper was in business for very long time. His son Nicholas was running the company when they started using the Bayard trademark.
It would help if you could post some pictures of the gun. I have a several Pieper catalogs and may be able to id the model. I own several Pieper guns, including a Bayard 28ga.
Pete
