This April 26, 1900, American Machinist Magazine article, by E. G. Parkhurst, describes the manufacture process used to make a Krag barrel. Although, not specifically naming the Krag or S.A., there is no doubt this 1900 article is describing the operations and steps in use at Springfield on Pratt & Whitney machines.

I posted this before, but below is a link to Scientific American, an article about a year earlier then the American Machinist article. Not as detailed as your findings above, but it may compliment it to some extent. The article starts on page 267 and continues on page 330. Also, see page 323 for a picture of a Krag tested to destruction.

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Articles from the American Machinist and Scientific American showed up together in a period "Engineering Index" under Krag-Jorgensen for those seeking information on the subject back in the day on page 786.

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I thought the threads on my Krag barrel were lathe cut. Dragged the old barrel out and looked at it with a 7 power loop and I am not sure. Some of the marks look like conventional single point lathe turning and some look like they could be milled as described along with the figure 12 of a thread milling machine.
I thought thread milling was a later invention. Live and learn. Even if this is not the Krag operation described it is very informative as to what was being done in that time period.

Parashooter wrote on Apr 18^th, 2019 at 3:13pm:

If so then the mill cut and soldering the front base would have already been installed in a separate timed or clocked operation. Possible, I guess. Too, bad all the ones that worked there are dead and can not solve the puzzle.
The article did mention drilling with a sensitive drill then reaming. If the reaming was with a tapered reamer that would fit and this could be Krag barrels described.   ?????
Went back and looked for a drawing of the drilling machine, not included, if it had been it might have had revealing clues.

Parashooter,
Went back and looked at the reamers and they sure look like 30/40. 1900 is probably too early to be tooling up for the 03-A3 Springfield.

Parashoooter,
I was actually agreeing with you the machinery discussed in the article is probably for the Krag. I thought they might have been tooling up in 1900 for the 03A3, but your pointing out the hole in the Krag front sight base makes it look very probable all the machinery is for Krags.

If it had been me I would have finished all that last bit of machine work (dove tail and rear sight holes) in one operation and soldered a finished base to the barrel later. They may have had a good reason for not doing it that way. Big whoopsie on my part.

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)!

A year after Edward Granville Parkhurst wrote this article, he passed away at the age of 71. American Machinist documented his life in their 8/22/01 periodical (page 955 in the link below).

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FredC wrote on Apr 18^th, 2019 at 11:01pm:


I figured you were referring to the early 1903.  I suspected that in saying 03-A3, you were actually referring to 30-03, which was the first (failed) cartridge fielded for the very early 1903 Springfields. 

FWIW, I find all of this simply fascinating!  If only we could find that Way-Back machine and take a field trip back in time to when the Krags were new!