Airsoft BB guns vary from simple spring action pistols to fully automatic full size and mini electric guns that shoot 12,000 BB's per minute through six rotating barrels. Although the majority of the models in the market are some where in the middle. All the guns propel their projectiles, BB's, by use of one these three systems:
Airsoft Spring Action
This is te most basic type of airsoft gun, a great choice for entry level purposes.This is a manually operated gun that must be reloaded after each shot by re-cocking the lever or slide of the gun.
Airsoft Gas Operated
These models can vary from low/middle end to very high end. The lower end models are usually gas operated, nonblowback. Higher models can include rifles or SMG (SubMachineGun). In the fixed slide or non-blowback type of gas operated guns there is a gas chamber that is reloaded after shooting several magazines. The gun is capable of semi-automatic and/or full automatic fire. In the gas blowback type, the slide moves back and forth like in a real gun when shooting. There is distinct recoil and gas chamber located in the magazine. This type of gas operated air gun is very realistic both in feel and action.
Electric Airsoft Gun
The top of the line in Airsoft Guns is electric airsoft guns, powered by a battery. They shoot around 750 rounds per minute fully automatically with superior reliability! And they don't have to be recharged as often as gas operated guns, and there is no heavy gas cartridges to carry. Normal operation, depending on battery size, can last anwhere from 600 rounds to 3,000 rounds. A basic rule of thumb for battery consumption and life is each mah rating a battery has is equivalent to firing one BB / pellet.