The Girandoni Air Rifle was a .46 caliber, tubular-magazine-fed, air-powered rifle that could fire 22 shots within a minute, each shot as accurate and lethal as black-powder muskets of the day. Can you say Assault Rifle?
The butt-stock was a removable compressed air tank, and could fire 40+ shots before needing to be replaced. Each rifle was issued with three tanks and a bicycle-style pump to recharge them. It took just 1500 pumps to charge each tank to the required 800 pounds per square inch, using a motion very similar to many current abdominal exercisers. Since the Austrian Army used the Girandoni between 1787 and 1805, perhaps this is the origin of the phrase attributed to former Austrian Arnold Schwarzenegger: “I’m here to pump you up.”
New Evidence on the Lewis and Clark Air Rifle – an “Assault Rifle” of 1803. By Robert D. Beeman Ph.D. Excellent and very detailed article by Dr Beeman explaining the history and technology behind this weapon. He was initially skeptical that Lewis & Clark carried the Girandoni air rifle, but the evidence favoring it was overwhelming.
Both of these videos demonstrate the musket and explain how Lewis & Clark used it to awe the Indians.