This single shot .22 Lr rifle was made in Germany prior to WW2. It was intended to be used as a trainer for both the military and civilians as it closely resembles the K98 rifle. 

This one was made in the BSW factory. Markings on top of receiver are BSM SUHL. On the side of the receiver Deutsches Sportmodell. 
On both the barrel and receiver is the crown over B and U. 
Bolt matches the serial number on the barrel.