I have a theory and ?'s on my Model 1917 quirks.

[Calif-Steve]

A M1917 with a serialized bolt can be reasonably assumed to be an ex-British weapon. The Germans and the Brits numbered their bolts. The US Army did not number its bolts. I received a CMP 6 million Garand with a numbered bolt. It was a WWII bolt and was clearly done in the National Guard or perhaps a University ROTC unit. But NOT done at Springfield. You will see Greek return M1903's with serial numbered bolts, again not done at Springfield, but rather done by the Greek Army. So US weapons will be encountered with serial numbered bolts, but a little education goes a long way. If only these things could talk!