Occasionally, you will see a sportered Krag with a confusing barrel.
It was an old 'gun-smithing trick' to improvise Krag replacement barrels from 1903 Springfield barrels.
Besides being smaller in diameter at certain points, a 1903 Springfield barrel may have coarse machine marks & a notch for a Springfield rear-sight /collar cross-pin, may lack rear-sight holes (for a Krag sight), may be around 23 inches long & have remains of odd lettering, and have an oddly machined extractor notch and breech-end.
Never seen a 1903 Springfield barrel up close. It would have to have a portion of the chamber cut off to ream for the smaller 30/40 cartridge. Depending on what the smith wanted for over all length would determine how much he cut off. Maybe there was a published guide so most came up 23 inches? Or did one company supply a lot of partially converted barrels so you see similar details in many examples? You example shows a course extractor cut extractor cut maybe done with a broach or shaper. Also indicative of a production set up using the known clocking of Krag barrels. The one Krag barrel I have on hand was done with a rotary mill cutter much like the one in my sporterizing photos.
Since this Springfield barrel had no rear-sight holes or Krag front-sight base to align, "easy-peasy" for a machinist with a lathe.
1. Machine-off enough metal from a .30-03 or .30-06 barrel-breech so that a .30-40 chamber-reamer can alter the chamber for the Krag cartridge.
2. Re-chamber with the .30-40 reamer.
3. Screw altered barrel into a Krag receiver until it stops against the flange of the action. Mark the barrel breech where the extractor slot is located.
4. Remove the barrel and grind the extractor-slot. (Then polish, draw file, re-crown, blue, or whatever).
5. Install barrel on receiver and add any sight-holes, dovetails, banded front-sights.
Good and safe enough for a 'Hunting' Krag, no Springfield Inspection or standards involved.
There was a time when .30-03 and .30-06 barrels were surplus and plentiful and a practical replacement for a 'roached-out' Krag barrel. Once a man was set up to do one, he could likely do them quickly by the score, (with likely improvised short cuts, guides, or fixtures).
BR, you have the procedure down on making a one off barrel conversion, from your description I gathered you had seen several with the same look.
If you see a bunch of these in a similar configuration, with the undersized portion of the barrel in the same spots and the extractor slot with the same tool marks one gunsmith/machinist was doing a heck of a lot of them or someone was supplying gunsmiths with an easy kit barrel. Otherwise you would see different finishes near the receiver. Pretty sure a 1903 had "fat" shoulder that butted up against the receiver. One smith would have lopped off just enough to clean up the chamber another would have lopped off 2'' and got on another part of the taper, with a different finish next to the Krag receiver. With no published directions or a wholesaler supplying a lot of gunsmiths with the same altered barrel each would have an entirely different look. If I had a pile of barrels and did one or 2 a month, no 2 of them would have looked alike. Different tools would have been in the machine that day affecting the finish or customer requests would have made each one unique. I kind of doubt that many gunsmiths would have had a shaper or special broach and fixture for the extractor slot. Most would have modified a woodruff cutter (like mine) or made one from scratch. A few might have made a sideways cutter and shaped them on a lathe, but that is slow and tiring process and each would have unique tool marks. Sure would be interesting to talk to someone old enough to have seen all these things.
In 1982, we built a Krag hunting rifle on a spare receiver. At that time Flaig's in Millvale PA still had a few converted Springfield replacement barrels. They had advertised them for Krags in the 1960's and early 1970's. They were new 1903A3 Remington barrels that were converted, shortened, re-chambered to 30-40 and had the extractor cut done.
My 1982 invoice from Flaig"s says I paid $58. It installed without any extra issues, we polished it and blued it and added the ramp front sight. You can just make out a faint RA and date at the muzzle end at 6 O'clock under the front sight. It didn't quite polish out and I left it that way.
Thanks for sharing your personal experience 'Cat Man'.
I forgot about Flaig's. They advertised gun-smith services in the "Rifleman" for Ages.
I had a Krag 'sporter' that was an economy rifle put together by Sedgley. The barrel was a recycled 1903 (.30-03) barrel, clearly marked "S.A. - 1905".
My Krag sporter (the one I will be using for bear hunting this Fall, hopefully) has a 1903 barrel marked R.I.A 1-09 for Rock Island Armory, January 1909. The barrel measured from muzzle to bolt face is 23 - 3/16". Teeth marks near the receiver. 1896 rear sight straddled over a dovetail.
I have a Colt Army Special chambered in 32-20 that dates to 1910. At some point in time it was rebarreled using the muzzle end of an M1917 Flaming Bomb barrel dated 6-18.
