15-round Cartidge Boxes were supplied Glued but not opened out…the Top of the carton was part of the Bottom, and laid out flat and extended…when it got to the Filling Plant, women workers took the long flap, threaded it thru the rectangular “tube” ( which had already been glued at the Carton factory) and either filled the cartons by hand, (Clipped ammo) or placed it in the magazine of the DWM Cartridge Box Filling Machine ( “ohne ladestriefen”) which, like a cigarette packer, shoved 15(loose) rounds at a time into the carton. The carton then passed down a converyor to other women who folded & fitted the top flap in place, and it was then sealed with the Label.
Although a lot of the carton suppliers were small local concerns, after 1943 when Speer took over Munitions control, there was a lot of shifting from the Big carton producers to the smaller factories, even over long distances, to use up over production in one area and compensate for Bombing Losses etc in others. Flat but glued cartons (due to the design) were easy to ship in large quantities.
Carton makers were Identified by an Embossed Logo in the cardboard ( rather than a “WaA” number.).
An analysis by Carton/Packet collectors of the different Logos should ID (a) how many there were,(b) where cartons from a particular Cartridge filling Plant always the same supplier © Possible ID of the carton makers, if “locally Linked”? and were there more different carton makers before 1942 or later? ( rationalization of production by Speer).
As to the use of 7,9 x33 labels and carton overruns etc, even the Czechs in the early 1950s Packed 7,62x45 in 7,9 cartons and adjusted the labelling ( also a “German” style label) accordingly.
The Carton question is an overlooked area of 7,9 production History.