Vic - not an easy question to answer. I can give some examples, but I can only address the subject of auto pistol ammo sold under the Herters brand name. Some 9 mm is made in the Czech Republic. It is a fair assumption from cartridge characteristics that it is from Sellier & Bellot, and has an odd abbreviation for Herter’s on the headstamp, “HRTRS” as I recall, which only saved them two spaces for spelling it completely out. Other Herters-boxed 9 mm Para is made in Russia, and has Russian headstamps. Their aluminum case ammo is made by CCI. I have Herter’s brand .380 Auto and it is made in Idonesia, with a “PIN” headstamp signifying “PINDAD.” It is possible that if I went thru my complete box collection, pretty much impossible for me right now as I am undergoing a complete reorganization of my files and of my box collection, I would find other countries.
It is very hard to tell who is making what these days, especially if the box is not specific - such as “Made in the EU.” You pretty much have to go on a box by box basis. Even that can be misleading, although I am not stating it is so on any of the Herter’s stuff. I mention it only because there are rules about how much of the components or loading procedures produce a product that must then be labeled as having been made in one country, even if much of the components are from other countries. I don’t know the specifics of these rulings, and they may differ from country to country.
I know that this makes the answer to your question about as clear as swamp water! It simply is, what it is!