While older German Guns had the duty bullet indicated, and still older ones showed proof load(bullet and powder)modern guns usually show only caliber( this is Austrian, however).I agree with Skeettx on the other thread,that the most likely load would be 180 gr. if it was built for "stock".If it was made to order, it would have been regulated to the ammo specified by the customer.If Borovnik has the records, it would still be necessary to test it, because there are differences between European and American ammo.American ammo may, or may not regulate.If you handload, you are likely to find a load that "regulates"anyway.
Mike