I wrote an article back in 2000 in "Muzzleloader" magazine entitled "The Short Rifles of the Lewis and Clark Expedition".
First, the rifle that appeared in American Rifleman in an article by Kirk Olsen is not an 1803-1806 production variant, it has components from a Type II rifle (1814-1819 production). Research by Jess Melot of The Rifle Shoppe clearly shows the distinctions.
Secondly, Harpers Ferry and Springfield Armories certainly never produced a rifle before the "short rifle" (also called "the iron ribbed rifle"), production which started with Lewis's visit in April 1803. This is borne out in numerous letters in official US government correspondance and arsenal lists of stores, which show only production for muskets and bayonets prior to 1803 (and were not talking about the incorrect 1822 records). How and why Carrick, Keller, and Cohan arrived at the "Model 1800" designation is beyond me. I have some doubts about the authenticity of the rifle they are promoting as a "Model 1800".
There is no evidence that Lewis's rifles were equipped with slings, and those listed were for muskets, as evidenced in various letters of the expedition, government correspondance, and arsenal records (zero parts for rifles in stores, with the exception of 16 rifle sights). We also have drawings from Gass's journal. The art of St. Memin depicting Lewis holding a long rifle or fusee has sling swivels, and it's obviously not a military arm.
As for Frank Tait's conjecture, he shows Model 1807 contract long rifles which were fitted with Harpers Ferry locks. These rifles were clearly made after the expedition, and in no way resemble the earlier contract long rifles of 1792, which originated from at least ten different contractors, made along their own personal styles, and were required only to be uniform in regards to having octogonal barrels of a certain length, thickness, and caliber. There are many letters attesting to the poor quality of these rifles, hence Dearborn's letter to Harpers Ferry arsenal master armorer Joseph Perkin to produce the "short rifle" (what we now call the Model 1803 Type I). I sincerely doubt Lewis would have picked out ten of the "best" 1792 era rifles, and only modify them by cutting them down, bore them to 30 balls to the pound, and add sling swivels. There is nothing in ordnance correspondence showing any such measures taking place (even before or after the expedition). More wishful thinking.
As for the authenticity of the purported "Model 1800" and its association with the L&C Expedition, there are several glaring discrepancies. For example, the lockplate does not fit into the mortise (notice the gap). Also, there is a mortise for the brass ferrule on the forestock, which was not present on early Model 1803 rifles- this was suggested in December 1803, long after Meriwether Lewis departed Harpers Ferry with his rifles, locks and spare parts, tomahawks, long knives, and iron frame boat. The stock appears to be from a Type II rifle. This rifle may have an original lock and barrel, however other parts are not from an Type I 1803 rifle.
Several years ago, a previous owner contacted me with the desire to examine his rifle. Unfortunately, I was out of state and could not meet him. As for forensic evidence, and given the fact that this rifle was advertised at auction for around $75,000, I propose that it be subject to non-destructive labratory analysis, to include dating the wood, x-ray of the markings, scoping the bore, chemical analysis of the metals, spectroscopy, etc., to actually determine its authenticity.
