'Skeet1' - Much to my surprise and against my early assumptions, I have come to believe all of the manufacturing, proofing, and finish operations were performed on Krag barrels, (including extractor notch, sight holes, front sight base, and index mark), prior to the barrel being screwed on to the receiver.

This had to require very careful gauging of parts and 'timing' of the barrel and receiver threads.

A lot of the manufacturing process was documented by 'Scientific American' in April and May of 1899.

Franklin Mallory used a lot of the 'Scientific American' articles in the early chapters of "The Krag Rifle Story".

If you enter Sientific American in the KCA Forum 'search window', you may be able to pull up some posts with manufacturing content.