Rick Hacker wrote an article in the February, 1981 issue of Guns & Ammo magazine about the Navy Arms Henry in .44 Rimfire. The title of the article is "The Iron Horse Rifle". Cutting to the chase, the article was essentially the story of one of the Henry Rifles that had been issued to U.P.R.R. surveyor by the name of Lathrop Hills. In 1867, he was killed by Indians in Wyoming and his Henry was lost in the sage brush. After a search that lasted 25 years, a man by the name of Peter Keenan (in 1917) found Hills Henry Rifle, which was engraved on the receiver forward of the side plates, with the letters U.P.R.R. In late 1981, Navy Arms decided to put out their own version of the famous U.P.R.R. marked Henry Rifles, limited to 100 guns total. These U.P.R.R. commemoratives were available and chambered in two calibers; .44-40 and .44 Henry Rim Fire. The article says, and I quote "Chamberings may be ordered in the historically correct .44 Rimfire (for which no commercial ammunition exists) or in .44-40". Today, these guns are rare. I saw one on an auction site several years ago, but it sold before I could place a bid. That gun was new in the box.