Headspace gauges caliber 9 mm Parabellum


I found these two gauges.

What country ?
What date ?



Chasspot - I can’t tell what the two odd marks are, but I will say that “G” and “N” (no-go and go gauges respectively) is the correct German Language abbreviation for these “Stahlpatronen,” as they were referred to in official German price lists for tooling. “G” is for some form of the word “Gross” indicating “oversize” (my German is terrible and I don’t know if it is “Gross,” “Grosster.” (is such a form even exists) or what), and “N” is for “Normal.”

I wish the other marks were clearer - the picture is fine; it is almost TOO sharp. They look, on my screen, somewhat like proof marks found on items (Guns and other ordnance material) from the WWI era, but I could be totally misinterpreting them, since I really can’t make them out well.

Again, though, I think they must be from a German Language country.


The mark on the right hand side of each gage appears to be a crown over the letters RC, which marking is described as indicating acceptance by or on behalf of the Revisions Commission of German army ordnance. This mark, as used on German small arms of the Imperial period, ordinarily indicates a component which has failed to pass regular inspection, and has been referred to a senior authority for review and acceptance. Jack


My guess is WWI German, but it is only a guess because I have never seen a WWI German 9mmP Guage.



I also believe that these German gauges date from WWI, and there are 7.9x57 gauges using these top markings reported to be from this era. These pistol gauges are described in German documentation as “Stahlpatrone G, größter Länge (Pistole 08)” and “Stahlpatrone N, kleinster Länge (Pistole 08)”.

John, I’m not sure if “N” stands for “Normal” because this is described as a minimal lenght gauge. Is there an explanation for this?


Perhaps N indicates niedrigster. In at least some contexts it is, I think, the opposite of groesster. Jack


I was told a long time ago by one of the German chaps that the “N” stood for Normal, because it was the gauge that the represented the normal (correct) length of a 9 mm case and therefore the action should close on it. It was in reference to the 9 mm Gauge. Years and years ago I wrote the first article of which I am aware of to this day, on these “Stahlpatronen.” I expressed that interpretation of “N” and it was not corrected by anyone in the U.S. or Germany. Of course, that does NOT mean it was correct. At least now I find that I did not just make up a German word-form, “grõßter” on this thread.:-)

I am surprised that I remembered that word in the back of my head, as after I wrote the article on 9 mm Stahlpatronen, I never again was able to obtain one in 9 mm. I did, however, have a fair collection of them in 7.9 x 57 mm Mauser.

I, too, have never seen one from the Imperial times, in either 9 mm or 7.9 x 57, although I did have one from the Weimar Period, 7.9 x 57, in my collection.

They are interesting looking gauges - very new looking though for something almost 100 years old if they are from Imperial days. They also look on my screen like they have a lot of tool marks. All of the gauges I had, both my two 9 mm Gauges that began my interest in them, and all 26 or 27 of my 7.9 gauges, were of an extremely high, smooth polish on the incredibly hard surface. On the 7.9s, marked on the sides of the “case,” one of the gauges was remarked for some reason at some time, and they failed completely in an attempt to polish off the old markings, settling instead for cutting an “X” through the remaining markings that they had tried to polish off, and putting the new markings on the other side. I should have photographed all those 7.9 gauges before they got away from me.


The length of the N gauge is 19.17 mm and 19.59 mm for the G gauge.

I found these in a small 9 Parabellum collection with this dummy and others common cartridges.



Joachim Görtz on page 68 of his book “Die Pistole 08” (edition from 2000) lists three gauge types as of the 1913 acceptance regulation:

“Stahlpatrone kleinster Länge” (19.10 mm according to the drawing he publishes) (shortest length steel cartridge)
“Stahlpatrone normaler Länge” (19.20 mm) (normal)
“Stahlpatrone grösster Länge” (19.50 mm) (greatest length)
So apart from G and N there should be a K gauge.
Terminology varied. The N gauge is also called “Stahlpatrone Normalmass” (normal dimension) in the same document. The others would then be K = Kleinstmass and G = Grösstmass.

Gently closing the toggle should show no resistance on K, give at most a very slight resistance on N and not close fully on G. (Tested with firing pin, ejector and extractor removed.)


Jochem, very interesting information. I wonder why the “N” gauge was listed as “kleinster Länge” in the 1930’s.


Fede, a very good question which I cannot answer. Joachim Görtz’ information dates from 1913, your table is from the 1930s. Having known him for many years, I consider his information as reliable as one can ask for.
It is quite possible that the K gauge was dropped and only N and G remained. (Today we also typically have only two types: GO and NO-GO). Considering the 1913 regulation: if the toggle closes on N (as it should for acceptance), it will definitely close on K, because K is shorter than N. So K is superfluous. The test with K (toggle should close on K) can be left out, because if it the toggle does not close on K, it will definitely not close on N and be rejected.
So my hypothesis is, K was dropped and N became the gauge for the smallest allowable headspace, AKA “kleinste Länge” (GO in modern parlance). G remained the NO-GO gauge. But this is only a hypothesis, because I know of no documentation giving proof to this assumption.


Concerning the apparent anomaly in headspace gage lengths between the 1913 regs and those of the 1930s: it would seem useful to actually measure the lengths of the early gages and the later ones to see if the shorter gage of the later date matches the 1913 small or normal. Jack