By using incorrect information , you will make incorrect assumptions . The M-95 bore Groove dia was always .329 . The .323 dia long rn bullets just rode the lands . This was common with all early military rifles . Accuracy was good enough , pressures were down and velocity was up . The Germans never used a .318 bore , nor a .323 dia bullet in Gew-88 rifles . The Gew-88's .3188 dia long rn bullet rode the lands on a .321 groove . Later the Germans switched to a larger short .321 Spitzer bullet , as a short or boatail bullet will not ride the lands as well or produce as much pressure as a long bullet . The M-95's later bullet was a .3286 boattail for machine guns , but would still work in the rifle's .329 bore.