Headspacing Mausers is an interesting exercise. It must be presumed that when the gun & bolt were mated at the factory headspace was within spec., but with an elderly military firearm with a matching bolt the headspace could have increased, and with the many military Mausers out there that come with mismatched bolts the only thing you can rule out is that it's not too tight if the bolt closes properly. In addition, the 7.92mm Mauser specs. have changed slightly and two sets of headspace gages are made for them, varying slightly by date of manufacture of the gun. The practical difference is very little, but that little might include some small difference is case reloading life.