[quote=“DocAV”]Copper Washed/Copper Clad:;;My bad…the manner of manufacturing the Russian (and Chinese cases is done at the Sheet Rolling Mill…the outer and inner copper “layer” is compression rolled onto the thin steel, such that the Copper bonds to the steel. It (“Bi-metal”) is then Punched and drawn into Cases. The Method uses the natural lubricant quality of the copper (in Steel dies)…if it was Steel on steel, there would be more wear and possibility of “seizing” ( same metals) The Only places where the steel is exposed is the edge of the Mouth of the case, and the extractor groove…hence the Laquering in these locations.
Germany did “electroplate” shells in the 1930s (Galvaniziert) using both Pure Copper and “Brass”; The “Eiserne Hulse” of WW I was electrolytic copper of Very Low carbon steel–"Iron"
The Later Nazi era cases were a Higher Carbon content (still mild but were called “Stahl” (Steel )
The Czech and some other Steel cases (Grey) are done by the Bonderising Process ( like Parkerising),leaving an Iron Phosphate surface etched, so that it holds Lubricant whilst Drawing. They are then “Hot dipped” as a finished cartridge, into special Lacquer (* saw the Machine at S&B, 1993). The Czechs inherited the Bonderising Process from Nazi Germany, who in turn filched the Patents from the French (Patented in the early 1920s); The French-made Bonderised cases during WW II (under Nazi control) and then took it up for a great part of their 1950s and 60s manufacture of all calibres ( .30 cal.;7,9mm; 7,65L Pistol; 9mm, etc.etc)
Doc, sounds like a good book should be in the making, thank you for all the info.
In short, I have always been told 7.62x25 Russian is loaded to higher pressures then the 7.63 Mauser, and you should not use the 7.62x25 Russian in a Mauser Broomstick. Do you agree ?