CNC POM Piston head

The CNC POM piston head from RetroArms is made of durable polyoxymethylene (POM) using precision CNC machining, ensuring high accuracy and reliability. POM is renowned for its strength and durability, contributing to a long lifespan.

Redesigned, counter-pressure piston head, modified according to long experience and customer feedback. The most noticeable change from the older versions of the piston head is the change in the shape of the air vents from cylindrical holes to grooves that better press against the o-ring seal. This creates a back pressure effect where the air pressure from the air vents expands the o-ring seal, pushing against the volume of air collecting in the cylinder and preventing air leaks.

Another change is the removal of the centering o ring, as it was causing the piston head to slow down as air was pushed into the cylinder. With the removal of the centering o-ring, the muzzle velocity is greatly increased. The centering o ring was added by RA in the past due to the use of nickel plated cylinders to avoid scratching the finish. Now stainless steel rollers are available so there is no scraping of the finish and no reason for the centering o ring.

The last change is to the piston head bearing. The heavy steel bearing is replaced with a lightweight plain bearing made of durable POM material that is fully adequate for even the strongest springs. In addition, this plastic partially absorbs shocks and increases the life of the mechabox.