I could be wrong, of course, but it seems to me that even a 2" group at 100 yards is ambitious given the coarse sights, unless you're under 40 years old and are a much better than average shot. Most Mauser rifles in decent shape are reasonably accurate, but the old inverted vee shaped front sight and vee-notch rear sight don't allow for the most precise shooting.

I bought an unissued M48 Yugo that shoots only fair. I can keep 'em all in the black at 100 yards, but not much better than that. The accuracy seems to be improving after a few hundred rounds, which I find rather odd; if a barrel needs to "wear in" it would seem as though it should do so more quickly. The fit and finish of this particular rifle are not as good as other Mauser rifles out there, in my opinion.

I also have an Oberndorf K98 Mauser made in 1941. This German weapon has a much smoother action that the Yugo, and groups much better in spite of being somewhat battered and war-weary. The pre-and early-war German Mausers that I have looked at seem extremely well made; the late war models are often really junky, especially the ones with stamped parts.

Good luck - - sounds like you're in for some fun!