Version 2.1 of the hop-up alignment system, designed specifically for M4 AEG HPA replicas using:
- Redline N7 Milsim G2 engine (second-generation compact HPA engine optimized for milsim configurations with excellent pressure control and response).
- Begadi Neptune Pro chamber (high-precision hop-up chamber with micrometric adjustment system and geometry optimized for HPA).
This system ensures perfect centering between the N7 G2 nozzle and the Neptune Pro chamber, eliminating BB feeding variations and maximizing pneumatic flow efficiency in high-performance builds.
Compatibility
| Component | Compatibility |
|---|---|
| HPA Engine | Redline N7 Milsim G2 |
| Hop-up Chamber | Begadi Neptune Pro |
| Base Replica | M4 AEG |
| Gearbox | V2 / ICS SPLIT |
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 Neptune Pro.
- 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 contact areas to achieve a clean fit.
- Apply dry lubricant or wax on sliding surfaces if frequent maintenance is expected.
2. Installation in the replica
- Insert the base into the lower and install the M3 inserts.
- Mount the rear clip aligned with the rear pin or the stock mounting point.
- Install the Neptune Pro chamber with the inner barrel; the top cap locks the assembly while keeping the barrel perfectly centered.
- Route the N7 G2 HPA line through the side clip to prevent sharp bends.
3. Final fixation
- Secure the rear plate using an M5 screw with washer for maximum rigidity.
- Verify that the Redline N7 nozzle enters the Neptune Pro chamber perfectly centered without lateral play.
- Perform dry feeding tests and adjust the Neptune Pro micrometric hop-up according to your BB weight and bucking.
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 your own 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:
https://lab.sychev.xyz/categoria/hpa-lower
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:
- Blackdraft Phoenix + Begadi Neptune Pro alignment kit for AEG (v2.1)
- 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)
Technical articles for this topic:
Frequently asked questions
What material and dimensions apply to Redline N7 Milsim G2 + Begadi Neptune Pro alignment kit for M4 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 Redline N7 Milsim G2 + Begadi Neptune Pro alignment kit for M4 AEG (v2.1) compatible with?
The published tags and categories identify this design with m4, redline n7, n7 milsim g2, begadi neptune pro, hpa, airsoft. Confirm the exact platform, revision, and mounting points before ordering.
How do I install or prepare Redline N7 Milsim G2 + Begadi Neptune Pro alignment kit for M4 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 Redline N7 Milsim G2 + Begadi Neptune Pro alignment kit for M4 AEG (v2.1)?
This design is intended for projects related to m4, redline n7, n7 milsim g2, begadi neptune pro, hpa, airsoft. 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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