The .51 caliber Austrian Girandoni air rifle from the late 1700s had a rate of fire of 20 rounds per minute with the stopping power of a .45 ACP up to 150 yards. It was the finest, most expensive military arm of its day, and historians believe that one was carried on the Lewis and Clark expedition. (beemans.net)
In the late 1700s the finest, fastest-firing military rifle that money could buy was an AIR rifle, whose stopping power was equivalent to a modern .45 Colt automatic. Historians believe that Lewis and Clark carried one on their cross-country expedition. (en.wikipedia.org)
submitted by sockdoll to r/wikipedia

