Rifle calibers were not marked clearly on the old German rifles, so some knowledge is asked for. Let's interpret the numbers: "111" is a ledger number for the month of proof. As these were only used by the Zella-Mehlis proofhouse, your drilling was made and proofed in that town, about 5 miles north of Suhl but at that time in another German state. "1.06" is the date of proof, January 1906. "118.35" is a gauge number like those used on shotgun bores up until now.These old-fashioned gauge number were used by the Z-M proofhouse up to about 1910. Suhl to 1912. Then they were replaced by millimeter numbers like "8.8". 118.35 tells us the bore or land (Not groove or bullet!) was larger than 8.64mm = .340" at the proofhouse, but smaller than the next gauge #, 108.49 = 8.89mm = .350". Small wonder a .355" 9mm Luger bullet does not enter the muzzle. A gauge # 118.35 is perfectly okay for the 9.3x72R, originally a blackpowder cartridge with very deep grooves designed for lead bullets. Today's minimum dimensions are bore: 8.75mm = .344", groove 9.25mm = .364".
BTW the term "guild gun" is an American invention, born out of ignorance on how the European guntrade worked! These guns were made by individual makers, even "name" ones like Sauer, the Merkels, Meffert, for the trade. Marking them with an adress was left to the country gunsmith who retailed them. Often those retailers did not bother to spend time or money on such marking, hence the many noname German guns.