It took me a lot of reading on late nights to get all the US ones straight. Not sure I can fit in the hours of study required for the advanced degree in rifle loony for non US rounds.
But if I had the time and money a prewar single shot and a drilling would be on the list of next projects.
Sure glad the next double gun get-together is far enough away so I don't get any bad ideas.

I used to only shoot shotguns and rimfires, then I made the mistake of getting a subscription to handloader.......