Treshkin - The Geco, DNG, DAG headstamps are confusing! For one thing, the Geco headstamp has been used off and on since before WWII right up to the present, and used on ammunition made in several different countries, at least Germany, Hungary (probably an unauthorized use of the Geco name), and Switzerland. The DAG headstamp also has a habit of popping up now and again.
DNG’s first headstamp seems to be from 1965, on a plastic short-range training round with the symbol date codes. The box for that is interesting, since it is commercialand is part of a group of boxes made for some time, in the pretty-much standard Geco commercial patterns, but without any city shown on the box - only "Made in Germany. The last use of the DNG headstamp on 9 mm Para seems to be from 1971, according to the Lew Curtis Book on 9 mm headstamps.
I am not even postiive what “DNG” stands for. It could be “Dynamit Nobel Genschow,” “Dynamit Nobel Geco,” or “Dynamit Nobel Actien-Gesellshaft.” I have no “favorite” interpretation among these.
A commercial-style box holding ball cartridges headstamped with the NATO mark and “DNG-68-20” also has no city in the address on the box. It is preceded by boxes showing Durlach and followed by boses showing Troisdorf, so that may represent the period of transition between the two.
I do know that when I visited the German Cartridge show in 1972, in a cab between the train station in, as I recall, Ettlingen, and the twos of Bergish-Bladbach that the show was in, we passed a sign showing the way to Durlach. I asked the cab driver about the “Munitionsfabrik” at Durlach and he said it had been closed for several years, but he didn’t remember exactly how long.
You had asked me also about the .DAG. 9 mm Blank. this blank is found with both red and blue lacquered seals at the closure of the rosebud crimp of the mouth. I have no answer for the use of the very tiny letters and the dots. It could be that the empty cases, or even the whole rounds, were made by someone else for GECO, but I can’t really be confident with that, as there appears to be little reason why they would do that, and while there are differents in size of the letters, and the shape of a couple of them the “D” in particular, I have seen or heard no evidence they weren’t made by Geco. Curtis’ book does not bring up the question. since these blanks are reported to be a launching cartridge for tear gas grenades used by the German police, it could be that the dots are only there to identify that it is not a normal noise blank. An identification like that would be likely for factory in-house purposes and perhaps for the police to know, only. I am not at all sure that the policemen using them would know.
As to the use of the symbol code dates by DAG, dates of 1983 and 1985 are the only ones reported by Curtis, known to be on 9 mm. I can’t speak right now to the question of other calibers. DAG dated headstamps on 9 mm are known as late as 1994, and probably well beyond. It seems to be a current headstamp - that is, in current use on military and some commercial ammunition.
Geco used the codes through at least 1985, with the earliest use known from 1965.
I hope this is of some help and that I didn’t just muddy the waters even more. I wish I had more definite information on this subject.