ADZZZYs Armoury show how they upgraded a Tokyo Marui MP5K AEG to have a higher rate of fire. This AEG arrived at the workbench sounding quite unpleasant. Upon opening the gearbox, it becomes evident that a previous technician left behind some questionable work. The original setup suffered from an incorrectly spaced piston that was actively colliding with the gears, a classic case of internet-acquired knowledge meeting a lack of real-world common sense.