CNC Rottary Chamber for AK

The NEBO Hop-Up Unit – CY version is a modern CNC chamber designed for selected AK airsoft platforms. It is built to significantly improve the original AK hop-up system and bring it closer to the performance and adjustability of modern M4-style solutions.

Most of the components are made from CNC-machined 7075 aluminum with a production tolerance of 0.05 mm. After manufacturing, the parts are automatically checked by laser measurement, helping ensure a very high level of fit and consistency.

The green CY version offers very precise Hop-Up adjustment through a large dial with position markings. An integrated O-ring helps prevent unwanted movement caused by vibrations, while the grippy dial surface allows easy adjustment even with gloves or in dirty field conditions.

The unit is compatible with standard 5 mm and modern 7 mm barrel windows and supports both AEG and hybrid inner barrels. The package also includes multiple tensioner parts and inserts, allowing better tuning based on barrel setup, bucking type, and BB weight. According to testing, the unit may also provide an energy increase of around 0.2–0.3 J without changing the spring or nozzle.

Important notes for the green version:

• recommended nozzle length when replacing the nozzle: 19.70–20.00 mm
• designed around the manufacturer’s original nozzle
• compatible with AEG and hybrid barrels
• supports 5 mm and 7 mm Hop-Up windows

Compatibility – green CY version:

• Begadi Sport (Cyma) AK Series – yes, very good
• Arcturus AK Series – yes, very good
• Arcturus AK Series (Begadi Upgrade Version) – yes, good
• LCT AK Series – yes, very good
• Lonex AK Series – yes, very good

Not compatible / exceptions:

• Arcturus PP19 – not compatible
• E&L AK Series – not compatible
• ICS AK Series – not compatible
• G&G AK Series – not compatible
• Real Sword AK Series – not compatible
• LCT Vityaz – not compatible
• AS VAL – not compatible

Package includes:

• CNC Hop-Up Unit made from 7075 aluminum
• 7075 aluminum adjustment wheel with position marking
• cover plate for the adjustment wheel
• countersunk screw
• 2x C-Clip for AEG and hybrid barrels
• Hop-Up arm
• 2x pressure springs
• brass screw for the Hop-Up arm
• brass barrel centering ring
• 2x O-rings for the adjustment wheel
• tensioner for 5 mm systems
• tensioner for 7 mm systems
• adapter for rubber tensioner
• 2x hard inserts (red)
• 2x soft inserts (black)