The expense of the weapon would've kept most from affording then and gun powder was cheap to manufacture by compairison. There are several variations of the air rifle that have been produced from the 1700's up and there is even a variation with a shield so the shooter could fire and not be easily hit. The history of these weapons is very neat and I didn't know that Lewis and Clark had one but I did a report on the history of fire arms in Jr high and discovered some really interesting things that should've taken off but never did.
As an example is the screw breach rifle that king George didn't think was effective. The trigger guard screwed out and there was a large hole in the back of the breach so you would load the ball first, pour the powder in, shut the breach, put powder in the pan and fire. Much faster and very accurate. Just imagine if they'd used that instead of the normal muskets that they had. Rate of fire would've increased as well as accuracy. It woul've devistated the American forces.
