In an effort to widen its potential marked for the C96 pistol, Mauser offered it in 9x25mm (aka 9mm Mauser Export) as well as the much more common 7.63x25mm cartridge. The 9mm cartridge was made by simply blowing out the bottlenecked 7.63mm case to a straight walled type and loading a 126gr bullet. The two cartridges has the same muzzle velocity (1360fps) and effectively equal ballistic coefficients, so the rear sight graduations were left unchanged (a very clever design feature!). In fact, the only distinctive feature of the 9×25 model aside from its bore and chamber dimensions was the addition of a small divot to the follower to improve feeding with he straight walled case.
Only about 150 examples of 9x25mm C96 appear to have been produced, based on the surviving Mauser order books. The cartridge was also used in the experimental C06/08 Mauser pistol, but it was really too powerful for pistols at the time and found a better home in submachine guns. The Swiss and Austrians both adopted it for SMG use (in the Steyr MP30/34 and the SIG/Kiraly guns).
Mauser Export C96 pistols are found with serial numbers in these ranges:
88,000-90,000 (with an “a” suffix)