Version 2.1 of the hop-up alignment system, designed for M4 AEG HPA replicas using:
- Blackdraft Phoenix engine (compact and affordable HPA engine with an excellent price-to-performance ratio).
- Begadi Neptune Pro chamber (high-precision hop-up chamber with micrometric adjustment and geometry optimized for HPA systems).
BlackDraft Phoenix: This version is a pre-2026 beta release that is not compatible with 2026. If you need it, you can request it.
This kit ensures solid and precise alignment between the Phoenix nozzle and the Neptune Pro chamber, maximizing feeding consistency and taking full advantage of the direct airflow from the HPA engine for improved compression and long-range shot grouping.
This template was created for Phoenix Beta, which was released before 2026, so if you need the 2026 version, just let me know and I'll put it together for you.
Compatibility
| Component | Compatibility |
|---|---|
| HPA Engine | Blackdraft Phoenix M4 HPA Engine |
| Hop-up Chamber | Begadi Neptune Pro |
| Base Replica | M4 AEG |
| Gearbox | V2 / ICS SPLIT (explicitly ICS compatible) |
What the kit includes
- Rear clip for mounting via rear pin or fixed stock.
- Base with housing for M3 inserts (optional brass).
- Side clip for routing the HPA tube/line.
- Front locking top cap designed specifically for the Neptune Pro geometry.
- Rear plate with mounting point for an M5 screw (additional reinforcement).
Installation and adjustment
1. Printing and preparation
- Print the parts with 65–80% infill.
- Lightly sand internal areas and contact surfaces for a clean fit.
- Apply dry lubricant or wax on sliding areas if you want easier maintenance.
2. Installation in the replica
- Insert the base into the lower and install the M3 inserts in their housings.
- Mount the rear clip aligned with the rear pin or stock mounting point.
- Install the Begadi Neptune Pro chamber with the inner barrel; the top cap locks the assembly while keeping the barrel perfectly centered.
- Route the Blackdraft Phoenix HPA line through the side clip to prevent bends.
3. Final fixation
- Secure the rear plate with an M5 screw and washer for maximum rigidity.
- Verify that the Phoenix nozzle enters the Neptune Pro chamber perfectly centered without lateral play.
- Adjust the Neptune Pro micrometric hop-up according to BB weight and field conditions.
Required components (not included)
- 4× M3 × 4.2 mm threaded inserts
- 4× M3 × 8 SHCS screws
Lower receiver recommendations
For maximum rigidity it is recommended to use the ICS metal lower receiver.
If you prefer to print the lower part, the following Gearbox V2 Lower “Universal Lower Part” models are compatible:
- Version 3
- Version 4.2
- Version 4.3 MTW
You can find them HERE.
3D printing parameters
- Approximate print time: ~1 h 30 min
- Recommended material: PLA+
- Layer height: 0.10 mm – 0.15 mm
Manuals
Installation and adjustment manuals are available in the Manuals section of the website or on the project’s Discord server.
Related products and articles
Similar product designs:
- GATE Pulsar-H + Begadi Neptune Pro alignment kit for M4 AEG (v2.1)
- Gate Pulsar-S + Begadi Neptune Pro alignment kit for M4 AEG (v2.1)
- Redline N7 Milsim G2 + Begadi Neptune Pro alignment kit for M4 AEG (v2.1)
Technical articles for this topic:
Frequently asked questions
What material and dimensions apply to Blackdraft Phoenix + Begadi Neptune Pro alignment kit for AEG (v2.1)?
The public product data does not declare a material or finished dimensions for this design. Check the images, downloadable files, and the exact manufacturing or printing setup before producing it.
What is Blackdraft Phoenix + Begadi Neptune Pro alignment kit for AEG (v2.1) compatible with?
The published tags and categories identify this design with m4, blackdraft phoenix, begadi neptune pro, hpa, airsoft, alignment kit. Confirm the exact platform, revision, and mounting points before ordering.
How do I install or prepare Blackdraft Phoenix + Begadi Neptune Pro alignment kit for AEG (v2.1)?
Read the installation notes in the product description, inspect the supplied files and images, and test alignment before final fastening. The required tools, fasteners, printing parameters, or post-processing depend on the specific build.
What are the real-world uses for Blackdraft Phoenix + Begadi Neptune Pro alignment kit for AEG (v2.1)?
This design is intended for projects related to m4, blackdraft phoenix, begadi neptune pro, hpa, airsoft, alignment kit. It is useful for a compatible repair, conversion, prototype, replacement, or custom build when the published fitment and project requirements match.
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