That was just the kind of site I have looked for but could not find! I tried to take a photo of my item but the wear and glare made the markings too indistinct to be of any use. Apart from the Oed imprint the case is identical in construction and markings to the 7,5 Feld Kanone M15 Skoda. Now you've solved the difficult bit for me I can dig a bit deeper. Many thanks!
OED is prsumably the factory that made the cartridges. The only example of an austrian cartridge has BMF which is Berndorf Munition Fabrik. I donlt know what Oed stands for but Styr rifles have a mark OEPY and the "OE" might stand for OEstereich - assuming that tpoudr cartridge is not from an entirely different weapon!