Please help me in identifying this ammo-7.9x57 German

Not really sure what this is. I found it in some of my dad’s old stuff. Headstamp says 13 35 P25 S* Any help identifying this is greatly appreciated.


You have a 7.92x57 Mauser cartridge, made in Germany in 1935, by Metallwarenfabrik Treuenbritzen G.m.b.H, Werk Sebaldushof.

I had a power outage in the middle of typing a response, that lasted two hours.

Jonny, you stole the words right out of my mouth.

Thanks guys for the quick response. I have no clue as to what he shot these out of because I’ve never known him to have a Mauser. I do know he told me once that he had some FMJ rounds that he used while picketing in the coal mines…

To fill out the reply to your question, this was one of the earlier post-WWI factories to make 7.9 under the post-WWI numerical code system.
The green primer seal tells us that this cartridge case is loaded as type s.S. ball (Schweres Spitzgeschoss)(heavy ball). It was pretty much, I think, the most common loading found in P25 cases.

On German ammunition of this era, the headstamp code identifies only the case maker. It tells nothing of the loading or who loaded it, with very rare exceptions, such as some dummy cartridges marked on the headstamp as “Ex.” which stands for “Exerzierpatrone” (Exercise cartridge, which is what we call a drill or dummy cartridge).

The “S*” on the headstamp indicates that the case is brass, of the improved type (72% copper as opposed to “S” brass which was 67% copper (nominal, I am sure).

Perhaps ist interesting to know the powder in your round was made by Rdf128 (Pulverfabrk Walsrode) the 4th lot of 1935 and the bullet was the P25, 12th lot of 1935.
The primer in your round was made by SKD (Selve-Kornbegel-Dornheim, A. G.) the 291 th lot of 1935.

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Here is the box Label.


Is there any reasons you guys call the cartridge “7.9x57” rather than 7,92x57mm IS?

No. The official name is 7,92 x 57 IS

In the US it is mostly called 8mm Mauser.
Please correct me when I am wrong.


Well, the problem is that the German army as originator of the cartridge never used a designation of the Erfurt-convention “7.9 x 57” type.
As can be seen from “Patr. s.S.” (its not 7.9 mm Patr. s.S.) on the label, caliber was not part of the designation. The designations were Patrone 88, followed by Patrone S etc. The same applied to rifles and machine guns: it was MG 42, not 7.9 mm MG 42.
You will find caliber only in manuals describing weapons characteristics: “Kaliber 7.9 mm”

Starting with Gewehr 88, the dimension tables (Maßtafeln) give the bore as 7.9 + 0.04 mm and the rifling depth first as 0.10, a few years later as 0.15 mm. This adds up to a groove diameter of 8.20 mm.

When after WW1 newly independent countries like Poland and Czechoslowakia, using former German machinery, manufactured small amrs and ammunition, they called the caliber not 7.9 but 7.92 mm (obviously the middle of the original tolerance range). This is, as far as I have been able to find out, the first use of “7.92”. Yugoslavia, by the way used the correct figure 7.9 until the cartridge was phased out in the eighties.

The German army called the caliber 7.9 right up to the end of WW2 (also for the assault rifle). The Navy had originally called it 8 mm (machine guns in Zeppelins, for example) and did this until 1943.

German Luftwaffe during WW2 decided to change bore tolerances slightly and from then on listed the caliber as 7.92 mm (for example in the FG 42 manual). In the new Bundeswehr, former Luftwaffe personnel dominated the weapons field. Consequently, Bundeswehr officially uses the name 7.92 mm x 57.

Considering that the German army as originator and main user of the cartridge called the caliber 7.9 mm, I think this is the number that should be used for the cartridge: 7.9 x 57. (Apart from the consideration that 7.92 and 7.62 are very similar and prone to mistypes or misreads.)

The above refers to the military cartridge. In civilian German use, it was originally exempt from the Erfurt convention and called “M88/S”. The situation then gets foggy, because civilian ownership was outlawed in the wake of WW1. In any case, the CIP decided on “8 x 57 IS”.

It is important to know that the German military did not (repeat not) change the bore dimensions with the introduction of Patrone S. Only the case neck (!) part of the chamber was made wider to accommodate the slighly larger bullet diameter. Bore and groove diameter remained unchanged. (Facts are very complicated, but thats the story in short.)

The similar cartridge 8 x 57 I (note the missing S) with its smaller bullet diameter and bore dimensions was strictly a creation of the German commercial gun trade. It has nothing to to with the German military.

“8 mm Mauser” is a misnomer, because cartridge and rifle 88 were developed by the military at Spandau, keeping Mauser deliberately out of the entire process. As a sort of compensation, the Mauser(!)-developed 7.65 mm, first adopted by Belgium(!) is named 7.65 … Argentine!!!