Technical information

Practical A.E.G Upgrade 2006

We found that using spacer for better FPS is effective and safe only for harder

and shorter springs. On softer springs (like the default TM ones) the small

increase in FPS has no real world significance at all. We have had a case where

a G36C was equipped with a very hard but short (about one third shorter than a

stock TM spring) custom-made spring capable of 450 FPS. By removing the 0.5

inch spacer from the piston we saw an instant drop of 50+ FPS. By adding a ball

bearing spring guide the FPS went back to 450~460 again.

Be very careful when using spacer with PDI springs. PDI springs have many

active coils, meaning the compressed length is quite close to the maximum.

Additional spacers may cause gun lock-up.

Different piston models have different inner diameters. You need to

choose spacers that are of a proper size – there shouldn’t be room for

these spacers to wobble inside the piston.

Spring

Guide

Spacer

Piston