Springfield Krag rifle builder.

[butlersrangers]

I have no idea what you are referring to in the Poyer book. Page 100 in the 2nd & 3rd editions has 'table 2-9' - with notes on Krag receiver changes.

There are many 'hieroglyphics' on U.S. Krag parts, that meant something to Armory workers 'back in the day', but, pose an enigma, now.

A lot of these odd markings indicated that a part had passed a sub-inspection, as it moved through the manufacturing process.

The Krag receiver went through something like 125 machining operations, as it went from a 6 pound forging to a finished 1 and 1/2 pound heat-treated product ready for assembly.

The Krag barrel went through approximately 30 manufacturing operations.

The markings on the Krag barrel breech are not a date or date code. They are believed to signify the 'Steel Lot' a barrel was manufactured from.
(This would be useful in 'tracking', if problems developed with barrels from a certain lot of contracted steel).

The 'bevel' or radius at the rear of your barrel-shank, would indicate the barrel was made sometime after June,1899. Poyer reports the change to the breech-face, from square to radiused corner, happened around serial number 213,000.

(Some Hoppe's #9 and a bronze brush should clean those spots of rust and crud from the breech-face and extractor-notch).

I altered your photo to show the radius that was added to the Krag barrel around #213000.
Attachment 116023