Ace 1 Arms HPA AR/M4 Airsoft Rifle – Inner Barrel (Semi-only-ETU)
£31.99
A replacement barrel section from ACE for the HPA AR/M4 platform, intended for technicians servicing or rebuilding an existing rifle. The semi-only ETU marking on this listing should be checked against your own gun’s setup first.
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Description
The ACE inner barrel is supplied as an internal replacement part for the HPA AR/M4 airsoft rifle. It is the barrel itself rather than a complete upper or a whole gun, so it is relevant when you are repairing, upgrading or rebuilding an existing rifle and want to fit a fresh bore without replacing the entire assembly.
The listing carries a semi-only ETU marking, so compare that against the trigger unit and firing setup in your own rifle before ordering. Because internal components differ between models, check the details shown here against your gun rather than assuming a straight swap.
- Inner barrel for the HPA AR/M4 airsoft rifle
- Supplied as an internal part
- Semi-only ETU marking on this listing
- Intended for repair, rebuild or upgrade work
It is aimed at owners and technicians who already know the rifle they are working on and want the barrel part for that build.
Additional information
| Weapon Category | Parts |
|---|---|
| Type | Inner Barrel |







