gate pulsar s begadi neptune pro alignment kit v2 1 m4

Version 2.1 of the hop-up alignment system, specifically designed for M4 AEG HPA replicas using:

• Gate Pulsar-S engine (compact HPA engine with integrated electronic control and design optimized for V2 gearbox).
• Begadi Neptune Pro chamber (high-precision hop-up chamber with adjustable tension system and reinforced design for HPA).

This kit ensures solid and precise alignment between the Pulsar-S nozzle and the Neptune Pro chamber, maximizing feeding consistency and making full use of pressure in high-performance HPA setups. Compatible with ICS split systems.

Compatibility

Component	Compatibility
HPA Engine	Gate Pulsar-S
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 guiding the Pulsar-S HPA tube/line.
• Front locking top cap for the Neptune Pro chamber.
• 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 the internal and contact areas for a clean fit.
   • Apply dry lubricant or wax on sliding surfaces if you want to make maintenance easier.

2. Installation in the replica

   • Insert the base into the lower and secure the M3 inserts.
   • Install the rear clip aligned with the rear pin or the stock anchor point (especially important in ICS systems).
   • Install the Begadi Neptune Pro chamber and inner barrel; the top cap locks the assembly in a precise position.
   • Route the Gate Pulsar-S HPA line through the side clip to avoid rubbing or bends.

3. Final fixation

   • Use an M5 screw with washer on the rear plate for maximum rigidity.
   • Verify that the Pulsar-S nozzle enters perfectly centered into the Neptune Pro chamber without lateral play.
   • Adjust the Neptune Pro hop-up tension according to your BBs and trajectory preference.

Required components (not included)

• 4× M3 × 4.2 mm inserts
• 4× M3 × 8 SHCS screws

Lower receiver recommendations

It is recommended to use the ICS metal lower receiver for maximum rigidity, especially in split systems.
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.