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Action Army Double O-Ring AEG Piston Head

Action Army Double O-Ring AEG Piston Head

£23.95
£23.95
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DETAILS

SKU: 68540935
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Action Army Double O-Ring AEG Piston Head — double sealed, CNC machined, and running on a Japanese ball bearing. Built for power tuned gearboxes where the spring is doing serious work.

A piston head does two jobs at once. It has to seal against the cylinder wall for the whole stroke, and it has to let the spring rotate freely as it compresses. Most budget heads manage the first and fight the second, which costs you energy on every shot and twists the spring out of shape over time.

This one is CNC machined, double sealed, and carries a Japanese ball bearing on the spring face. Action Army describe the bearing as significantly improving how the spring works around its own axis, which is the technical way of saying it lets the spring wind and unwind instead of dragging.

They recommend it specifically for power tuning, and that is the honest place for it. On a stock rifle it is a refinement; on a heavily sprung build it is the difference between a spring that lasts and one that goes out of true.

Specifications

Specification Detail
Type Flat, double sealed AEG piston head
Bearing Japanese ball bearing on the spring face
Manufacture CNC machined
Stated purpose Recommended by the manufacturer for power tuned builds
Durability Described by the manufacturer as extremely durable
Manufacturer code A04-002
Weight and diameter Not published by the manufacturer

Good to know before you buy

Fit it with a spring guide that also bears. A bearing at one end and a fixed face at the other only solves half the problem, and the spring will still fight you.

Check your piston first. A good head bolted to a cracked piston body buys you nothing, and the first tooth is where to look.

Flat heads suit most builds. There is no porting here, so if you are chasing a very specific cylinder volume you may want something else.

No weight or diameter figure is published. Action Army give the construction and the intended use and nothing dimensional, so if your build is sensitive to piston head mass, ask us before ordering.

Frequently asked questions

Why does the bearing matter?
A main spring tries to rotate as it compresses. If the head will not let it, that energy is wasted and the spring slowly goes out of true.

Is this worth it on a stock rifle?
It will not hurt, but the manufacturer aims it at power tuned builds and that is where the difference shows.

What is it made from?
It is CNC machined and double sealed. Action Army do not publish the alloy specifically.

Does it come with the o-rings fitted?
It is supplied as a double sealed head, so the sealing is part of the part rather than an extra.

Do I need a bearing spring guide too?
Strongly recommended. Bearings at both ends is what actually frees the spring up.

Will it fit my piston?
It uses the standard AEG piston head fitment. If your piston is an unusual one, tell us which and we will check.

⚠ Do not overtighten it. A piston head screwed down hard enough to preload the bearing defeats the point of having one, and on a plastic piston body it is a good way to split the boss.
💡 Titan Forge Airsoft tip: Change the head, the o-ring and the spring guide together. All three are fighting the same problem and doing one of them is half a fix. More in our spare and upgrade parts section.