There are at least 2 different types of air rifles which may have been used by L&C. This issue has been and still is discussed by gun collectors. I think this video is way off. There is mention of the air tank being repaired during the trip. The gun most often credited had a round air tank suspended under the forearm. As for use it is mentioned that a goose was shot during the trip with the air gun. The Expediton went down the Ohio River to Clarks Plantation[Present day Clarksville Indiana] before heading west. During one of the many stops along the river they displayed the air rifle. It was at one of these stops that the gun was fatal to a human being. A woman was accidently shot and killed during a Demo of the air gun. I doubt very much that the early[Red Ryder] had that much to do with the L&C expedition.
See, I didn't know a woman had accidentally been killed but had read a deer was killed in a demo for Indians who were amazed the white men could harvest the air. Shame on me -- I have the published notes from the Corp. Maybe they meant "dear"?
I don't recall the deer incident. They shot a goose on the river. The NDNs were amazed. I really doubt the air rifle had much to do with their safe trip. They were impressed by the trappers skill with their rifles. The NDNs robbed them all winter on the coast. One of the trappers shot I think Capt. Lewis in the hip. This may have been an early "Fragging".