It may be a 6.5x54 Mauser, not Mannlicher-Schoenauer. A different case with a standard 8x57-type head size. A quite popular roebuck chambering during the 1920s-30s, most often seen in Mauser Kurz and Schmidt & Habermann M21 short actions. But here it is most likely built on an ex-military M98 action. "Germania Waffenwerk A.G." was noone else than J.G. Anschuetz, Reissmannstr.22, Zella-Mehlis, after WW2 refounded in Ulm, renowned for their target rifles.