[chestnut ridge]

The 1903 was made for about 40 years; and there must have been
many variations and subcontractors for the bolts. I would like to
know the different bolt codes and in which rifles they would be
"correct."

[Sunray]

The best place to ask is on the Springfield forum at www.jouster.com. Mind you, there weren't many subcontractors or variations. Springfield Armoury and Rock Island Armoury were the only manufacturers of the 1903. Remington made 1903A3's and 'A4's.

[Jim Watson]

Remington made 1903 and 1903 Modified before the A3.

The bolts are pretty much interchangeable anyhow, you can tell a lot by the angle of the handle and the shape of the safety lug. I think the nickel steel bolts were marked N or NS and Remington production were marked R. But my book is not in reach to be sure.

[Jim K]

I agree on the Jouster forum for M1903 questions. John Beard is the expert on Springfield bolt markings.

Many of the markings on Springfield bolts are a steel lot code indicating the steel maker, not the maker of the bolt itself, which would have been SA or RIA. The marking can determine if it is in the right serial number range.

There were several makers of replacement bolts in WWII, one of which was the United Shoe Machinery Co., which marked its bolts "USMC" and gave rise to the myth that rifles with bolts so marked were "Marine Corps" rifles and worth twice as much as "ordinary" Springfields.

Jim