Edward,
There are 30 rounds with many variations on the headstamp. Three examples are:
41 oxo St+ 4
41 dnf St 1
44 pfo St+ 48
Many other ordinance codes represented. I havn't been through identifying them all yet. Curtis at
www.cartridge-corner.com has been a help in making sense of the headstamps. In the order I've written them, I understand these markings to mean:
1 year of manufacture
2 ordinance code
3 Steel case (brass apparently would be just S or S+
4 lot number
I did not get an answer as to the significance of the + or it's absence. Any ideas? On one the + appears more like a small arrow, but I think it is just a poorly formed +.
As for the .38 special rounds, I am not convinced that a luger could not shoot them. I should add that I have absolutely no intention of doing so for I fear that it may not be safe either for me or the gun. But I think that they may have been fired by my father in law, years ago. I just tried chambering one and it appears to fit quite well. It may not project quite so far back from the chamber, but the extractor picks it up fine and therefore I believe the firing pin would reach the primer. A side by side comparison shows very little if any difference in case dimensions. The main visual difference is in bullet shape and length. I assume the powder charge is also different but I havn't checked up on that. My worries center around the bullet differences and how they may not match the chamber internals.
Thanks,