You have a very tastefully done sporter that, as others have mentioned was probably done after WW1. She has the old style "GERMANY" export mark on her barrel as well.
I have a feeling she may be an ex-Kar98 or an ex-Gewehr 98 but many of her military markings and attributes have been scrubbed and polished off. Is the receiver a large or small ring ? The receiver is definitely a M98 based action which was retained and used by the German military from the mid 1890s up to end of the 1940s so you have a very long track record of functionality and reliability.
The markings on the bottom of the receiver are worker and work type related markings of which the meaning and interpretation today has been lost to time.
Keep a close eye on parts like the the bolt stop, bolt pieces (even the firing pin) as not all military markings and/or inspection marks may have been removed completely. You may see a Gothic style letter underneath a crown which would indicate Imperial German military use at one point up to 1918. If you require reference pictures for what typical markings would look like, feel free to have a peak at the "Thinking about a Gewehr 98" thread near the top of the Milsurp board.
I really like the look at the spoon handle and rear sight set up, it was well thought out. The stock appears to be walnut and, like the work on the rest of the rifle, was well done.
As far as what you may shoot, I would slug her bore and perhaps pay a quick trip to the gun smith as there were a number of commercial oddball 8mm calibers in the 1920s that are obsolete now. The standard military cartridge was 7.92x57mm with a ~150 gr bullet for Germany just before and during WW1.
In any event, you have a very nice sporter that will get some real attention at the range from fellow shooters.
Thanks for compliment, tokguy

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