Unknown Rifle or Shotgun

Firearms | Armes à feu
1

Hello,
I have a gun that is listed in my papers as a shotgun with caliber 16/65.
However, the weapon actually has two rifled barrels, like a double-rifle. The side lock is marked “Berger.”
Can anyone help identify what kind of firearm this is, and which cartridges are required to make the weapon shootable again?

Thanks,
Christoph

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2

My uneducated guess is it is a 16 gauge slug gun. Maybe it originally had a second set of smoothbore barrels. If not then you live with the poor pattern using shot shells. Maybe it was never meant to be used as a “shot”gun.

3

on one side lock you got the name of the city A BERGER… what is marked on the other side lock ?