I have thought about the term obsolete, and the only cartridges I think are not obsolete by Mule Deer's definition from the dictionary are the 5.56 Nato, the 7.62X39, and the 9mm Parabelum, though that nomenclature is obsolete. I am not sure if the .22 rim fire exists or not anymore.
In all honesty no cartridge was ever in general use worldwide.
Certainly the 264 is made from current use technology: the belted magnums seem to be surviving along with the .473 family, while none of the Rums, Saums, and other newer iterations seem to be achieving non-obsolescence.
It seems the term obsolete is about worthless in the description of cartridges, though I think the .43 Egyptian qualifies, just to show I am not dogmatic about it.
Mule Deer I appreciate your input, I think you have good ground here for a thoughtful article.
