FWIW: I recently sold a Krag 'Sporter' that was fabricated from salvaged parts by R. F. Sedgley, Inc.

The barrel was a 'Rod-Bayonet' 1903 Springfield barrel, made in 1905. It likely was chambered for .30-03 before being shortened at the breech end, re-chambered for .30-40, and 'notched' for the Krag extractor.

The receiver threads on a Springfield barrel would be the same form, diameter, and pitch, as a Krag barrel.

The Springfield barrel's outside contour is different and diameters are smaller than on a Krag barrel.

I don't know all of what was involved in fitting the Springfield barrel to the Krag action. The 1905 barrel was basically 'upside-down' on my 'sporter. The "S.A. 1905" mark was on the bottom instead of the top.

This Sedgley/Krag had a tight chamber, but, accepted factory ammo without problem. The headspace was on the minimum side. The bolt locking-lug had been lapped so that the rear of the bolt-rib made contact with the receiver.

Workmanship was crude, but, functional.

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