Airsoft Guns
Airsoft guns (also known as Soft Air guns by some manufacturers, are spring, electric, or gas powered air guns that fire small spherical plastic pellets of either 6 mm or 8 mm diameter (0.24 or 0.32 inches). Inexpensive airsoft guns are often used as toys, while more expensive models may be used for firearms training or in the sport of Airsoft, which is similar in concept to Paintball.
Types
Spring powered
Spring-powered airsoft guns are single-shot devices that use potential energy stored in a spring to launch an airsoft pellet down the barrel of the gun. The user must cock a spring gun prior to each shot. This is typically achieved by pulling back the slide (pistols), bolt (rifles), or the grip on a shotgun, which in turn compresses the spring and makes the gun ready to fire. Because of this, these guns are by definition incapable of automatic or semi-automatic fire
Gas powered
Gas-powered airsoft guns use pressurized gas to propel pellets. These guns are capable of automatic and semi-automatic operation. The most common gases used are “green gas” (which consists of a mixture of propane and a polysiloxane lubricant) and HFC-134a. Less commonly used gases include “red gas” (which is actually HCFC-22), CO2 and nitrogen/high pressure air. Red gas is usually avoided unless the airsoft gun has undergone modification, as its relatively high critical pressure can cause damage to the airsoft gun. CO2, nitrogen, and high pressure air are less common because they need to be stored at higher pressures than “green gas” or HFC-134a.
Automatic Electric Guns
Electric-powered airsoft guns typically use a rechargeable battery to drive an electric motor, which cycles an internal piston/spring assembly in order to launch pellets. Automatic and semi-automatic operation is possible which gives these guns the popular name “automatic electric guns” or AEGs. These guns often attain muzzle velocities of 200 to 400 ft/s (60 to 120 m/s) and rates of fire of between 300 and 1100 rounds per minute. They are the most commonly used and widely available type of airsoft gun.
These type of guns were developed in Japan and the Japanese company Tokyo Marui dominates the market. In a Tokyo Marui AEG, the motor drives a series of 3 gears mounted inside a gearbox. The gears then compress a piston assembly against a spring. Once the piston is released, the spring drives it forward through the cylinder to push a pellet into the chamber, through the barrel, and forward from the muzzle. Many manufacturers have now more or less replicated this basic model, adding reinforced parts or minor improvements.
