Martin: The U. S. military .30-40 ammo was quite corrosive with the early smokeless powders and mercuric priming. If proper cleaning was not done, soon after firing, there was damage to the bore.

I have a model 1899 Krag, similar to yours, that was used for Hunting. It has a pristine bore and a replacement 'banded front-sight'. The barrel is a original Krag barrel, but, it is 22&1/4 inches long. It has to be a rifle barrel that was shortened. When I got the Krag, it was in a horribly re-shaped Krag carbine stock. I put it in a cut-down rifle stock and it is probably my favorite Krag for shooting!

The Krag was very inexpensive and popular, as a Hunting rifle, in the 1920s to 1940s. There were surplus parts and barrels. There were commercial 'after-market' sights available. Sometimes 1903 Springfield barrels were altered to .30-40 for use on the Krag. The 1903 Springfield front-sight was a cheap and viable replacement sight. Altering Krags was common work for professional and amateur gunsmiths of that era.

IMHO - Barrel replacement seems to have been relatively common on Krags used for Hunting. (Who wants a crappy bore)?   

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