With the 3 Ring Krupp Steel, the tubes had to originate with Sauer. It looks like they also made/assembled the tube set. Sauer was centered around production models while the Brothers Merkel had the flexability to produce special order models. The side frame reinforcement is also something seen on many Merkels. Is there are a serial number on the left side of the rear lug or on the water table? Also is there a date stamp on the underside of the left tube? Either Timner's initials were A.F.W. or earlier he advertised as A.F.W. Timner. He knew quality like many of the firearms merchants.
Kind Regards,
Raimey
rse
