The design was based on the rotating barrel locking mechanism of the Roth–Steyr M1907 but replaced the external striker with a spur hammer ("Hahn") and simplified disassembly to allow for field stripping under adverse conditions.

A small batch of the M.12 pistols was also manufactured in the 1930's for the Austrian army, but these deliveries had to be kept secret due to Austria being still bound by the provisions of the Treaty of St. Germain.

After Germany annexed Austria in 1938, the German Police ordered 60,000 M1912 pistols rechambered to 9mm Parabellum which remained in service until the end of World War II.

[4] To load, the slide is pulled back to expose the action, the clip is inserted along the guides and the rounds pushed into the magazine.

A machine pistol version of the Steyr M1912, designated as the Repetierpistole, was commissioned at the end of 1915 and developed at the Österreichische Waffenfabriksgesellschaft under Major Franz Xaver Fuchs, commander of Standschützen-Bataillon Innsbruck II.

Topping off the magazine, either by feeding two 8- round clips or manually loading each cartridge by hand, was also slow and cumbersome..

It is because of this extended magazine that the weapon earned its "P16" suffix, standing for Patrone 16 ("16 cartridges") - contrary to some reports, "P16" is not a reference to the year 1916.

Only a handful of examples exist today, most of which are low serial numbers, leading some experts to estimate that less than a thousand were made (Thomas Nelson claimed around 900).

[7][8][5] After Germany annexed Austria in 1938, the German Police ordered 60,000 M1912 pistols rechambered in 9 mm Parabellum which remained in service until the end of World War II.

Pistols in police service were distinguished by the eagle emblem above the trigger and most noticeably a "08" stamp on the left side of the slide, to show that they chambered German 1908-type ammunition.