Most contemporary AEGs have a mechanical system inside their gearbox that houses three gears and a motor to allow the transfer of electrical energy into mechanical energy. Pulling the trigger completes the electricalcircuit from the battery to the motor.

When you pull the trigger, the motor receives power to engage the first gear (bevel), which in turn, engages the second gear (spur), before activating the third gear (sector). The sector then pulls the piston back and compresses the spring, while a small nub on the sector drags the tappet plate back, retracting the air nozzle. This enables the next BB to slot into the hop-up.

Next, the tapper plate returns to its original position and chambers the BB. Finally, the piston is released by the sector gear, allowing the springto shoot back and launch the piston through the cylinder to force pressured air out of the nozzle and fire the BB.

You can lower the FPS on your AEG by replacing the spring with a softer type of spring. Generally, airsoft guns will fire between 10 and 13 FPS less for every 5-spring strength lost. So, if your gun is currently shooting around 300 FPS and you drop 10 strength from the spring, it will shoot somewhere between 274 and 280 FPS.