Strangely-worded question!

ALL U.S. Krag rifles were made in the U.S, at Springfield Armory.

They started with *1, and went into the high 480xxx; so yes, there WOULD be one numbered 231. In fact, I once (1970s) handled #230, here in California - and that gun is now owned (small world) by a friend (and a contributor here) in Wisconsin, who purchased it about two years ago via mail, from somewhere else.

*up until around 20, they were marked "No. 1", "No. 2", etc.