Two things come to mind about your rifle. One is that hoards of these Krags were bought back in the 20s and 30s for a couple dollars each and cut down to make into easy-to-carry hunting rifles. All kinds of cut downs were made by well known gunsmiths as well as many done in garages and basements. Military Krag rifles were long and heavy. So, shorter barreled ones were easier to hunt with. Any length barrel was better than a long one.

The other consideration is that the muzzle was damaged, as you implied, and someone cut an inch or two off to recrown and make more accurate. That may be why your rifle is an accurate one. Even terribly worn and pitted bores can produce good shooters if the crown is clean and symmetric.

There may be other reasons why yours was cut the exact way it was but these are two possibilities. There are all kinds of sporterized Krags for sale out there and many are great shooters.

It would be nice to know more about the "faked" rear sight. These have popped up now and then with mainly 1896 carbine sights since they are so valuable. Can you post some pictures of this sight and the faked "c"s? The Krag Collector's Forum website has some pictures of faked "c" stamps for comparison. The "c" is often humped up and proud around the stamping compared to a clean deep strike on authentic ones.