This IS an interesting subject. One thing I think we can rule out is that stars on Russian ammunition identify case material. There are stars on cases of brass, brass-washed steel and copper-washed steel, and triangles on all three case materials as well. I can see no rhyme or reason myself to the use of those two symbols on Russian small arms ammo. For a period after WWII, many different factories used the stars or triangles at the 9 and 3 O’Clock positions on the headstamp up until a time, when the headstamps became uniformily two-place with maker’s code at the top and date at the bottom. I am not including artillery in this - I don’t know a thing about the stuff.
I would agree that on most, not all, military headstamps the entries all have meaning - militaries in general are not disposed to having meaningless figures “doll up” the headstamps of their ammunition, although I feel there are many exceptions to that. However, on ammo destined for the civilian market, certainly, for many manufacturers and most eras, there are decorative use of symbols on headstamps, especially stars. Headstamps, both military and commercial, with stars at the 3 and 9 O’Clock positions on the headstamps are legion in number, and in one case, Kynoch 7.63 x 25mm, it was the ELIMINATION of the stars that meant something on the “K B” headstamps - that the cartridge was 7.65 x 25mm Borchardt instead of 7.63 x 25 Mauser. It would boggle the mind to believe that in every case this common headstamp design had some special meaning.
I do not, and cannot, dispute the idea that on Russian small arms ammo every single entry on every single headstamp has a definite meaning. I am not inclined towards that theory, but again, do not have the knowledge to dispute it. It appears that no one of our hobby does, as no one in the years I have collected have ever published any documentation to that effect.
Of course, none of us is privy to everything a manufacturer does, especially in the military field, and especially when it comes to countries that had despotic leadership where virtually every little thing concerned with military equipment and affairs was secret. As late as the very early 1960s, when I started collecting cartridges, many markings on German WWII headstamps were not known to collectors, and some of the guesses we made turned out to be just about as wrong as they could be (but in truth, some proved to be correct). and that was some 15 years after the war had ended.
Syrian military rounds, for example, with stars at the 3 and 9 O’Clock positions, seem to be the norm, regardless of the caliber. I have at hand samples of that in .32 auto, 9mm Makarov, 9mm Parabellum and 7.62 x 39mm.
I share Liviu’s hope that eventually, older records will be found in many countries that will teach us much more about ammunition in general and headstamps in particular. I think we have made great strides in knowledge the last 30 years or so, but I don’t think we have climbed completely out of infancy on the subject yet. I know that I haven’t.