Airsoft AEG Piston and Piston Heads

The piston's purpose is to use the sector gear to compress the mainspring and then use that stored energy to push air, while the piston head's purpose is to create an airtight seal inside the cylinder to efficiently compress that air. The benefits of upgrading them include improved performance, enhanced durability, greater air seal consistency, and reduced wear on other gearbox parts, which can lead to higher velocity and a more reliable airsoft gun. 

Piston

• Purpose: The piston is drawn back by the sector gear, compressing the spring inside and storing energy. When released, it is sent forward by the spring to force air out of the cylinder.

• Benefits of upgrading:

◦ Durability: Upgrading to pistons with stronger materials, like steel teeth, reduces the risk of breakage, especially in high-stress builds.

◦ Weight: Lighter pistons can reduce stress on the gearbox and help prevent PME (Piston-Motor Engagement) in high-speed builds.

◦ Energy bias: Heavier pistons can be used to more efficiently use heavier BBs, contributing to a phenomenon known as joule-creep. 

Piston head

• Purpose: The piston head is at the front of the piston and contains an O-ring that creates a seal against the cylinder walls. As the piston moves forward, it pushes the air in front of it, with the O-ring ensuring that most of the air is forced out through the cylinder head and barrel.

• Benefits of upgrading:

◦ Improved air seal: High-quality O-rings and precise manufacturing create a tighter, more consistent seal for better FPS consistency and efficiency.

◦ Reduced noise and friction: Some designs are made to be quieter and reduce friction, which can extend the life of the gearbox components.

◦ Enhanced airflow: Some heads have optimized porting to improve airflow during the compression and decompression cycles.