Mr. James K makes a good point about the large number of different weapons, mostly carbines, using proprietary cartridges during the Civil War. One thing is that none of those different cartridges were considered standard in any sense of the word. But if any of them had been used in large enough numbers (that is, because there were large numbers of weapons that used them), it may have been different. As it was, virtually all small arms used in the Civil War had a useful life of little more than twenty years. They were produced in huge numbers but quickly became obsolete as breechloaders using metallic cartridge came along, just as they themselves had made flintlocks a thing of the past.
There were lots of new cartridges introduced after the Civil War, some still with us, if not exactly in wide use, others almost forgotten. The same is true of a lot of other cartridges, which in spite of being used a great deal around the world, are on the road to obscurity, though it will take a long time for some just because of the sheer numbers. But when no new firearms are made for them, that will happen. But who can tell what Ruger will make next year? How about a No. 1 in 6.5 Japanese? An SP-101 in .38 S&W. You laugh! I've seen a Security Six in .38 S&W and Ruger made something in .303 British, which by the way is the same as a certain 7.7 Japanese.
The day of the proprierty cartridge is not over, either. Apparently gun makers felt no reason to make their new guns to chamber someone else's cartridge, even for military use. So the only gun, I think, to chamber a .30 Luger was a Luger, except of course, for Ruger.
You know, now and then my wife will ask me some gun related question and one she asked was about Ruger and Luger.
Shoot low, sheriff. They're riding Shetlands!
Underneath the starry flag, civilize 'em with a Krag,
and return us to our own beloved homes!
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