I agree with Lew that these cartridges, with a commercial headstamp of B DWM B 480C, and in commercial-style packaging, likely date from the second half of the 1930s. There are a couple of clues to this. One is the box-end marking "Erosionssicher. (next line illegible in the photo here due to some sort of tape obscuring it) und rostfrei (visible portions: “Safe from erosion and rust free.” Another is the form of the name. Beginning in 1922, DWM changed its name to Berlin-Karlsruher Industrie-Werke A.-G. Then, in 1933 it was changed again to "Berlin-Karsruher Industrie-Werke AG, vormals Deutsche Waffen- und Munitionsfabriken. In June of 1936, the name was changed back to just “Deutsche Waffen- und Munitionsfabriken AG,” the designation on your box. Since the ammunition is non-corrosive, your box would almost have to date after 1936.
It would be good to see a picture of the headstamp on the cartridges from this box. To date, I have never seen a Berlin-Borsigwalde 9mm 480C cartridge with the old style serif letters, that were changed, I believe, in the latter half of the 1920s.
Regarding usage, following WWI many Mauser “Red Nines” (as well as other 7.63 mm variants) were converted to a fixed-sight, 3-9" barrel (barrels 4" or longer, I believe, were prohibited by the Treaty of Versailles’ provisions, hence the 3 and 5/8" and the 3 and 3/4" so-called Models 1920 and 1923 commercial Lugers, most all reworks from earlier military pistols). Some of the broomhandle Mauser conversions were dated, with the only reported date of 1920. Many of them had unit markings in various places on the pistols. These, seemingly invariably, were police markings, and were deciphered with the help of the German collector Reinhard Kornmayer. These markings were at least partially described in “Waffenverwaltungsvorschrift: Vorshrift für die Polizei Preussens, published in Berlin, in 1932. An explanation can be found on Page 104, Chapter 9, “Model 1896 Postwar Reworks,” in the book The Broomhandle Pistol, 1896 to 1936,” by Erickson & Pate.
Regarding these Red-Nine reworks, while done c.1920 primarily for Police, there is no reason that they would not still have been in some use in the late 1930s. Between that, the commercial style box marked as containing non-corrosive ammunition, the Mauser 10-shot stripper clips, and the style of the label, my opinion is that your box was made primarily for the Police, and not for the military other than, perhaps, the Waffen-SS who were known to use some Mauser C’96 types, mostly though the 1932 Schnellfeuer version in 7.63 mm. Of course, some German Officers of the Wehrmacht were known to have carried the broomhandle Mauser in various forms, probably privately purchased by them, so these same box types could have been offered for sale to “qualified” purchasers as well. Likely, there is no way to either positively or negatively prove that at this point.
Other sources used here:
“System Mauser,” by Breathed and Schroeder, pages 128 & 129
“Handbuch der Pistolen- und Revolver- Patronen,” by Erlmeier & Brandt, pages 254 & 255