OK lets see if I can decipher this--- The following is not set in stone as I am no expert. The info is from the set of books mentioned previously.
The action is basically a Martini type but the system (innards) is unknown as the rifle would have to be dissembled.
AW==Adalbert Wolf - Barrel Maker There are several AWs but only one listed as a barrel maker.
7.7mm ==bore, Most likely a 8.15x46R
10.12==should be the date Oct 1912 of proof.
176==Proof house serial??
B,G,U proofs ==B first proof,U second proof,G rifled barrel proof. These are the most common proofs -B,G,U. and can be found anywhere on a rifle.
GB and 14 ==???????
Go here and poke around, you will find it interesting
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