You have a K98k. There are two lengths, about 9.5 and 12.5. The 12" was adopted in 1940 so your rifle is right on the border, could be either. Use a stiff wire, run down the rod hole till it hits bottom and mark it at middle of front sight band, pull out, measure. Simple! Or move rear band forward and if you see a oblong piece of metal in stock on bottom, if so, it is a 9.5".
Good luck on an original, likely will not have any serial on it for that late a rifle and repro's are very difficult to tell from original.
Last edited by dave; 09-25-2016 at 08:42.
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