This is the pre-WWI method of German proofing. 118.35 is the bore gauge of the rifle barrel and corresponds to 9.3mm.

The other common gauge measurement for the 9.3mm bore was 108.49, the next size up.

Instead of the decimal point you often encounter a "slash" which would appear as 118/35.

You have a 9.3mm of some sort. You should do a Cerrosafe chamber cast to further explore what you have.

Curl

www.RoscoeStephenson.com

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