Air pistol

An air gun is any kind of small arms that propels projectiles by means of high-pressure compressed air or other gases which involves no chemical reactions, in contrast to explosive propellant of a firearm which 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. The first air guns were developed in the 1500s. The guns have been used in hunting, sporting and warfare. Air guns use three types of power, depending on the design: spring-piston, pneumatic and compressed carbon dioxide.

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 both matchlock and flintlock muskets), and discharged much 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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