CNC Stainless Cylinder – Type B (240–289mm)

RetroArms CNC stainless steel cylinder for AEG guns
Selecting the correct cylinder type helps match the air volume to the barrel length, which is why RetroArms offers Types A to E for different barrel-length ranges. The cylinder is precision CNC-turned from 1.4541 stainless steel. Subsequent thermochemical treatment creates a surface with a hardness of 630 HBA and a black finish that also provides protection against corrosion. For correct movement of the piston head inside the cylinder, we recommend lubricating the cylinder with silicone oil rather than grease, as an excessively viscous lubricant can increase resistance and slow down piston-head movement during firing.
How to choose the correct RetroArms cylinder type according to barrel length?
The correct ratio between cylinder volume and inner barrel length is an important part of a properly assembled AEG. RetroArms therefore offers several cylinder types with different port positions and usable volumes. When choosing a cylinder, primarily consider the length of the inner barrel. The extended Type E is a separate version designed for the corresponding SR-25 / PSG-1 gearbox configuration.

RetroArms cylinder typeRecommended inner barrel lengthApplication

Type A
130–239 mm
Standard AEG gearbox

Type B
240–289 mm
Standard AEG gearbox

Type C
290–369 mm
Standard AEG gearbox

Type D
370–650 mm
Standard AEG gearbox

Type E
470–650 mm
Extended cylinder ( plus 10 mm) for SR-25 / PSG-1 gearbox

Warning: The listed ranges represent the recommended barrel lengths for the individual RetroArms cylinder types. Type E cannot be substituted for a standard Type D cylinder based solely on barrel length – it is structurally extended by 10 mm and requires a correspondin..