ok, its a v.Dreyse, SN 5721 or is it 5121 ?, its old, I know when it was made.
its a 0,71", its possible to made ammo but the problems are evident.

the ramrod is missing, the trigger guard could have been half steel, half horn or completely horn.
with more pics I can say what it was, the trigger plate have holes speaking about it.
metal looks good to me, not so much work if the barrels looking good inside.

the stock is a real problem, someone with knowledge would find a way to restore it or you made a new stock. what happen, is it burnt?