Mod Mauser rifle - identification

[pawleyc]

I recently inherited a rifle, but need some help in identifying when it was made, and the caliber. I know it's a pre-WWII hunting rifle. It is marked "Mod Mauser J. P. Sauer & Son, SUHL." on the top of the barrel. There is no caliber marking on the side of the barrel, but the receiver side has S/N: 115249, and some sort of proof mark saying "2,67 g C R P" with "St. m. G." underneath. The top of the receiver in knurled. THe barrel is octagonal, becoming round and is about 21" long. Around the shank, it says "GUSS-STAHL-KRUPP-ESSEN." It has a metal capped pistol grip, and a floor plate with a release lever. I also see the markings "04" on the bolt, the rear site leaf, and the top of the front rim of the rear site.