Modify APS Aluminium Piston

Lightweight aluminum piston with a stainless tail for the APS series

This piston combines an aircraft aluminum alloy body with a stainless steel tail and a Teflon ring that cuts sliding friction inside the cylinder. The reduced weight lets the piston accelerate forward faster once released.

Cocking effort and compatibility with APS gearboxes

It also lowers the effort needed to cock the bolt, making stiffer springs easier to live with day to day. It replaces the factory piston in APS series gearboxes.