The 1st (of three)"American Machinist Magazine" articles, describing Springfield Armory manufacture of the Krag, dated March 22, 1900, mentioned 10 Pratt & Whitney rifling machines of the latest pattern.

The article promised: "The tools used in this work will be fully described in an article soon to be published, and need not, therefore, be further referred to at this time".

I believe the above, April 26, 1900, article that I posted, to be the 'promised' article. It appears to describe the manufacture steps used on Krag barrels.

I understood the front-sight procedures the same as 'Parashooter' did and figured the front-sight hole was for the blade pin.

I believe that the front-sight base becomes the 'fixed reference point' for other operations: barrel index-mark, timed barrel threads, extractor-slot, front-blade slot & pin hole, and rear-sight holes.

(The barrel breech is 'faced' prior to final barrel profile machining - operation 12. The front-sight - operation 15, is installed, brazed and shaped, after barrel is profiled and outside polished - operation 14).

The described 'Perry system' is an interesting process. (I never imagined).
Preparatory to 'turning' the outside contour of the barrel, a steel collar was positioned around the middle of the rough barrel and 'soldered' in place with 'molten' type-metal. This structure served as an interim support-bearing during machining of the exterior barrel profile.
(The outside of the barrel took shape and was polished, after finish-reaming of the bore, but before the rifling process.

After rifling, but before 'Browning', the barrel is chambered with rough, mid, and finish reamers.

I will never view a Krag barrel the same again. An amazing amount of labor went in to each one. Barrels were not made like we would make them today.
They were intended to be interchangeable - as best I can figure.

(Thanks to Knute1, for bringing American Machinist Magazine articles to our attention)!