I should not be so lazy. Here is all the information I can find easily about these, all
from the few 9x19 mm SD Geco boxes in my collection.
The first loading I have information for is from 1965, with the cartridge having the weight and
appearance of a standard 9 mm Ball round with bullet weight of 8 grams (124 grains). The
only ID for the round being “special” is that instead of the normal Geco bright-red primer seal,
the color is a Burgandy Red, very dark. The box label indicates this is “Sonderanfertigung für
die Fa. Carl Walther, Ulm.” Label information indicates the velocity at V10=280 m/sec(919 fps)
with a powder charge of 0.255 grams Ngl. P.P. (3.8 grains of nitroglycerin (?) based pistol
powder, Coopel Los 18." The bullet weight of the 124 grains is confirmed by the total weight
of the cartridge, which is 186.9 grains (12.11 grams). Cartridge headstamp is + Geco 41-65.
The “+” is actually the NATO mark of “+” in a circle.
Another box, containing ammunition headstamped “GECO 9mm Para” and having a normal red
primer seal and CNCS RN FMJ bullet is labeled “9MM x 19 Weichkern
Sonderlaborierung 10.0 G Geschoss,” and is “Los DAG 1/76.” As far as I can translate
"Sonderlaborierung" to English with my poor knowledge of German is “Special Laboratory
Experimental.” Bullet weight is 10 grams (154.3 grains). This is probably the box for the round
Vlim shows on his wonderful little boards. Bullet weight was confirmed, by the way, from the
full weight of the loaded cartridge, 14.40 grams (222.3 grains).
I have a box for “9 MM x 19 PARA 10.0 gram VMR-Geschoss für schallgedämpfte Waffen, Los DAG 1/80,” but it is empty so I can only report what is on the label. I assume that “VM” stands for “Vollmantel” (full metal jacket) but I don’t know what the “R” stands for, unless is is simply “rundkopf” (round-nose in English).
The final box is similar to above, except says "9 mm Luger 10.0g Vollmantelgeschoß für schallgedämpfte Waffen LOS DAG 2/82.
The first box mentioned is a standard blue, red and yellow commercial box of the style of the 1960s wtih a typed, white over-label (likely reproduced from a hand-typed master label). The other three boxes are all contract-style plain buff-tan boxes with white labels with red printing.
That is the best I can do. I have no catalog information for any of these rounds.