Identification help needed

[gunrunner100]

I picked this Mauser rifle up a few years ago and am just trying to get some information about it. I'm thinking it is one of the "guild" guns that were prevalent in Germany.
Front receiver ring (left) has "2.75 G.B.P." on it along with "S.G." under that marking. Barrel is marked with "7.8 mm" which I assume to be a 318 bore. Dual set triggers, full matted rib on a 23 3/4" barrel. There is one proof mark on the receiver and the barrel which appears to be a crown with an "N" underneath it. No serial # on it, but there is a # 10 that is on a few of the parts which could be an assembly #.
Poor storage has led to surface rust and staining on the metal. The stock is very light, typical of a stalking rifle with a leather buttplate and a slight cheek piece on the left side. Checkered on the wrist. Stock is in good shape other than missing some wood on the forend...?
Any information would be appreciated. I'd like to restore this, depending on what I find out.

 

[9.3mauser]

It appears to be an Erfurt small ring mauser from the first world war. The military marking have been filed/ground off the receiver ring, which is why you can't find a serial number. The original barrels were the standard 'S' .323" bore, but I can't tell from the pics if it's been rebarrelled or not. Looks like somebody spent some extra time and effort re-working this one.

 

[John303]

I have one that could be similar, it would be appreciated if you post some pics of the whole gun, both sides, top, and bottom. Might have more comments / ?s then. Well worth refreshing IMHO. --- John303.

 

[Baribal]

From the metal work, it looks like those of GECO Mauser (Gustav Genschow & Co.) or similar "Gunmaker and Wholeseller" of that time period. The proofmarks show it was proofed after 1898 and prior to 1912, as the (crown over) N with 2.75 g G.B.P. indicating the proofload of 42.35 grains of Special Military Flake Powder (Gewehr Blattchenpulver). This means it was proofed for a pressure of about 60 000 PSI (which should match the 8X57 IS).
It may be hard to find who exactly made it as the proofmarks may have been those of the orifginal proof, when the gun was proofed for service, as the aftermath of WWI was somewhat confused and the German had to get rid of a lot of military guns, which they converted to commercial guns, sometimes without re-proofing. I have seen weird bores in 9X57 (off-center or out of round) which you would never seen if proofed and / or inspected.
Was I you, I'd simply slug the bore to make sure what it is, a .318" or .323" bore.