I have just traded for an old hammer drilling. 12x12x ?. It is made by "D. Sauerbrey --ULM". The barrels are "Kruppscher Stahl". A marlin 444 fits in the chamber of the rifle barrel but is too small.The gun has German black powder proofs used after 1950 among others. Anybody know anything about this maker?

Please give the right stamps and all what they wright on the gun,Riflecaliber is Maybee 9,3X72R,an old blackpowdercartrige.
Ulm is an old gunsmithcity,Walther is now there.

I have 9.3x72R combinations guns. 444 will not fit their chambers. You may have 9.3x74R a much more powerfull cartridge.

Dr. Duc Can you give us the bore diameter and the diameter at the rear of the chamber. As you look in the chamber does it appear to be a straight case or a bottleneck?
If it is bigger than a 444 Marlin and bottlenecked in might be the 10.3x60R Swiss.
You can get a barrel for your Blaser in that calibre. You must use at least a 10.2 calibre in the Swiss province of Graubunden. The 10.3x60R is used there.

To really figure this out, you are going to have to slug the barrel and get a chamber cast.