His name was Ole Herman Johannes Krag, and his dates, b. 1837, d. 1916, are well-documented and reliable. He entered the military at age 17 and was later assigned to work at the Royal Arms Factory in Kongsberg, Norway, at which he eventually became the director. Krag worked with Erik Jorgensen to develop the Krag-Jorgensen rifle, a bolt action military rifle of the late nineteenth century. All-in-all, he seems an unlikely person to have made a name in American military history, but the Krag-Jorgensen rifle, caliber .30 (now called the .30-40 Krag), was adopted by the U. S. Army in 1892. It was the first bolt-action repeating rifle to be used by American forces, and it was also used by Norway and Denmark.
October 23, 2011 was a beautiful day in my neck of the woods, sunny, quite warm for October, and a bit breezy. A great day to be at the range with one of my editions of the Krag-Jorgensen, a model of 1892, made at the Springfield armory and updated there to the standards of the improved Model of 1896, as were nearly all of the early Krags as time passed. This arm has the appearance of a Model 1896 carbine, but it is actually a cut-down rifle fitted with a carbine stock, a common thing to find with Krags. When I found it the walnut stock had a good coat of varnish and a reblue job that gave it a very nice appearance and completely prevented any future collector value. Its mechanical condition and function were excellent. I have described the attachment of an aperture sight, using JB Weld, in an earlier post. This rear aperture works well with a 1/16th inch front bead.
For ammo I had brought a box of Winchester factory loads carrying 180-grain Power Point bullets. Remington markets a similar load, and these seem to be the only factory loads still available for the Krags. Following my usual practice, I set targets out at 50 yards and then fired a series of four-shot groups. Two consecutive groups, both measuring less than one inch center-to-center, are shown in the picture. 
These were fired from a bench rest using the aperture sight with a target of appropriate design. The groups are not centered in the bull, but I could easily adjust the sight for that when needed. It is the group size that I was looking for here. My chronograph measured an average velocity of 2311 feet-per-second for these Winchester loads and the rifle functioned very smoothly, a common trait of the Krag rifles.
I have said it in other posts and will say it again. Shooting old guns, when it can be done safely, is a lot of fun and it is always a real kick to get accuracy performance like this from an old military rifle. I hasten to add that there is nothing really special about my Krag. Since it came to live with me I have done nothing with it except to shoot it and give it routine cleaning. It has had no bedding or trigger work. I think you could expect to have similar performance from any Krag with a good action and decent bore. And by the way, this level of performance, while not in the class of a .30-06, would allow taking deer to at least 200 yards.
For his service in arms design and fabrication, Ole H. J. Krag was awarded the rank of Lieutenant Colonel in the Norwegian military. He had a wife and children, but there is little other biographical information for him on the net. I have not found a detailed biography, and know nothing about his personal traits. Spending time with his rifle, however, has given some insight into his talent.