Airgun

An air gun is any kind of small arms that propels projectiles by means of mechanically pressurized air or other gas (shooting involves no chemical reaction), in contrast to explosive propellant of a firearm (shooting involves an exothermic chemical reaction). Both the rifle and handgun forms (air rifle and air pistol) typically propel metallic projectiles, either the non-spherical pellets, or the spherical BBs. Certain types of air guns (usually rifles) may also propel arrows or darts.

Air guns represent the oldest pneumatic technology. The oldest existing mechanical air gun, a bellows air gun dating back to about 1580, is in the Livrustkammaren Museum in Stockholm. This is the time most historians recognize as the beginning of the modern air gun.

In the 17th century, air guns, in calibers .30–.51, were used to hunt big game deer and wild boar. These air rifles were charged using a pump to fill an air reservoir and gave velocities from 650 to 1,000 feet per second (200–300 m/s). They were also used in warfare, the most recognized example being the Girandoni air rifle.

At that time, they had compelling advantages over the primitive firearms of the day. For example, air guns could be discharged in wet weather and rain (unlike matchlock muskets), and repeatedly discharged faster than muzzle-loading guns. Moreover, they were quieter than a firearm of similar caliber, had no muzzle flash, and were smokeless. Thus, they did not disclose the shooter's position or obscure the shooter's view, unlike the black powder muskets of the 18th and 19th centuries.

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