Not Isaac. This one has one of Charley's barrels and the barrel is stamped "30 Newton".
(You need to Login to view media files and links)Charles Newton was an early builder of high velocity and high power rifles, 1910 to the late 1920s. He came up with this one in 1913. Back in the late 50s, there was a wildcat called the .30/338, or the .338 Winchester Magnum necked down to .30, a popular conversion for the 03A3 then available from the DCM for less than $20. Another name for the same cartridge was the .30 Belted Newton. If you ground off the belt, it had the same dimensions as the .30 Newton cartridge. Not a pipsqueak cartridge. The factory load (by Western) advertised a 180 grain bullet at 2860 fps. The cartridge was loaded by Western Cartridge Company until about 1938.
Shooting a Krag chambered for .30 Newton is not a good idea. It might be possible to chamber a Krag for the cartridge, but it is simply too large to work in the magazine.
If you look carefully at the barrel, it is stamped "Buffalo Newton". Charles Newton formed four Newton rifle companies. The first one appeared in 1914, with the rifles built in Germany. Bad timing. WW1 cut off the supply and the company failed. The other 3 were formed sequentially after WW1. All failed, one after another. The last one was called "Buffalo Newton" IIRC because the plant was in Buffalo, NY. When the Buffalo Newton company failed, there were some completed rifles on hand and a lot of parts. The guys who bought the stuff at the bankruptcy sale assembled some of the parts into rifles (I have one) and sold the remaining parts, including barrels, just as parts.
I think someone laid hands on one of the barrels, cut off the breech or chamber end, threaded the newly-cut end to fit a Krag and ran a Krag reamer into the barrel. My Buffalo Newton has an entirely different barrel profile at the breech. My barrel has Newton ratchet rifling, not conventional lands & grooves.