Welcome to TFL Misko,
I have numerous high-end airguns (exceeding $1000 each) and some are capable of pumping out lead at over 1000 feet per second. That’s faster that a .22 long rifle.
I wouldn’t consider using one for self-defense, although early models (around the turn of the century) were popular among the “gentleman class”. There were large bore air pistols and air powered “cane guns”.
Would a modern airgun kill? With correct shot placement, you bet it will.
Airguns are very popular in the UK, due to the heavy legislation on firearms. People use them to hunt small game for food or varmint control. I think they are limited to something like 12-15 foot pounds of energy.
An interesting side note is that airgun silencers are popular and widely used in the UK.
As far as the Austrian air rifles mentioned by 4V50 Gary, Napoleon had standing orders to his troops to KILL any opponents found with one. These air rifles were large bore and could kill a man at distance. “Snipers” were not looked upon with any favor back then and were considered cowards.
Skyhawk
[This message has been edited by Skyhawk (edited March 31, 2000).]