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AirsoftParts NBU Ribbed Cylinder – Full (400+ mm)
AirsoftParts NBU full cylinder is a polished stainless steel upgrade part for NBU / Bore Up air seal systems in AEGs with long inner barrels from 400 mm. The enlarged 24.7 mm inner diameter provides a higher air volume than a standard cylinder and requires an NBU piston head and NBU cylinder head. The smooth polished surface helps reduce seal friction.
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14,76 € In StockAirsoftParts DURAL 2013 NBU Piston HeadASPARTS011
AirsoftParts DURAL 2013 NBU piston head is a CNC-machined piston head made from EN AW 6012 T6 duralumin for Bore Up air seal systems. The enlarged NBU version works exclusively with the corresponding NBU cylinder. It features 9 holes for pressure-assisted sealing, a guide O-ring, an axial ball bearing and a lightweight design weighing 11.4 g.
14,76 €Out of stock
16,87 € In StockAirsoftParts Silent Cylinder Head NBUASPARTS016
AirsoftParts NBU silent cylinder head is a CNC-machined head made from EN AW 6012 T6 duralumin for Bore Up air seal systems in V2 and V3 gearboxes. The integrated sealing collar with a large 70 ShA impact pad helps seal the assembly and cushion piston impacts. The electroless nickel-plated finish provides high hardness, wear resistance and low friction.
16,87 €In Stock
10,95 € 16,87 € In Stock-35%AirsoftParts Cylinder Head CLASSIC NBUASPARTS018
AirsoftParts CLASSIC NBU cylinder head is a CNC-machined head made from EN AW 6012 T6 duralumin for Bore Up air seal systems in V2 and V3 gearboxes. Two O-rings provide sealing in the NBU cylinder, the shaped 70 ShA impact pad cushions piston impacts, and the electroless nickel-plated finish provides high durability and low friction for smooth NBU nozzle...
10,95 € 16,87 €In StockReduced price!
3,34 € 5,88 € In Stock-43%AirsoftParts NBU Duralumin NozzleASPARTS066
AirsoftParts NBU duralumin nozzle is a precision CNC-machined nozzle for NBU / Bore Up air seal systems, made from EN AW 6012 T6 duralumin. An internal O-ring helps seal the connection with the cylinder head and reduce air leakage. The nozzle is designed exclusively for use with an NBU cylinder head and weighs only 0.8–1.3 g depending on the length variant.
3,34 € 5,88 €In StockReduced price!
4,19 € In StockAirsoftParts Cylinder Head Shims (0,5 mm)ASPARTS101
AirsoftParts cylinder head shims are designed to precisely adjust the position of the cylinder head inside the gearbox. The set contains 3 stainless steel shims with a thickness of 0.5 mm, which can be used individually or combined as required. This practical service part allows the cylinder head position to be adjusted without irreversible modifications...
4,19 €Out of stock- SA Silicone Grease (50 g)
SPARMS439
Specna Arms silicone grease in a practical 50g package is an essential service lubricant for airsoft gun maintenance. It is particularly suitable for O-rings, seals, AEG pneumatic systems, GBB valves and HPA systems. It helps reduce friction, protects sealing components from drying out and extends their service life.
6,34 €Out of stock - SA Silicone Oil Spray (150 ml)
SPARMS444
Specna Arms silicone oil spray with a volume of 150 ml is a universal maintenance product for airsoft guns. The low-viscosity silicone oil easily reaches O-rings, seals, valves and moving parts, reduces friction and helps protect rubber and plastic components against drying out and ageing.
3,81 €In Stock
AirsoftParts NBU Full Cylinder for Bore Up Air Seal Systems
AirsoftParts NBU full cylinder is a component of Bore Up air seal systems for AEGs that differs from a standard cylinder primarily by its enlarged 24.7 mm inner diameter. The larger cross-section combined with the full non-ported design provides a higher usable air volume, which is why the manufacturer recommends this version primarily for builds with long inner barrels of 400 mm and more, such as various AUG or AK configurations. Due to the enlarged diameter, the cylinder must be combined with a corresponding NBU piston head and NBU cylinder head; standard versions of these two components are not designed for this cylinder. The cylinder is made of stainless steel, and its polished surface provides a smooth, low-friction working surface for the piston head seals. The manufacturer also specifies concentric machining. The cylinder weighs 25.3 g, has no external cooling grooves, is designed for V2 and V3 gearboxes with the corresponding NBU air seal system, and the maximum recommended spring is M170.
Key Features
NBU / Bore Up Design
The enlarged 24.7 mm inner diameter provides a larger cross-section and higher air volume than a standard cylinder, which is the main characteristic of an NBU / Bore Up air seal system.
Full Volume for Long Barrels
The non-ported design uses the full working volume of the cylinder, and the manufacturer recommends it primarily for AEGs with inner barrels 400 mm long or longer.
Polished Stainless Steel Surface
The cylinder is made of stainless steel with a polished surface, providing a smooth working surface and reducing friction of the sealing elements as the piston head moves.
Designed for a Complete NBU Air Seal System
Due to the 24.7 mm inner diameter, the cylinder must be used with an NBU piston head and NBU cylinder head. Standard versions of these components are not dimensionally compatible with the cylinder.
For V2 and V3 Gearboxes
The cylinder is designed for V2 and V3 gearboxes equipped with the corresponding NBU air seal system. The manufacturer specifies a maximum recommended spring of M170.
NBU Cylinder Type Table by Inner Barrel Length
| Type | For Inner Barrel Length |
|---|---|
| Ported | 200–400 mm |
| Full | 400–550 mm |
Technical Specifications
- Type: full NBU / Bore Up cylinder for AEG
- Size: NBU / Bore Up
- Material: stainless steel
- Maximum recommended spring: M170
- Surface finish: polishing
- Inner diameter: 24.7 mm
- Cooling grooves around the outer circumference: no
- Weight: 25.3 g
- Compatibility: V2 and V3 gearboxes with corresponding NBU air seal system
- Required piston head: NBU / Bore Up
- Required cylinder head: NBU / Bore Up
- Recommended inner barrel length: 400 mm and more
Frequently Asked Questions (FAQ)
Can the NBU Cylinder Be Used With a Standard Piston Head and Cylinder Head?
No. Due to the enlarged 24.7 mm inner diameter, according to the manufacturer this cylinder must be combined with a corresponding NBU piston head and NBU cylinder head.
What Is the Difference Between a Standard and NBU Cylinder?
An NBU / Bore Up cylinder has a larger inner diameter and therefore a larger internal volume. This model has a 24.7 mm inner diameter and requires corresponding NBU air seal components.
What Inner Barrel Length Is This Cylinder Designed For?
When selecting the correct cylinder type, inner barrel length is therefore a key factor, but for the correct calculation of Volume Ratio (the ratio of cylinder air volume to barrel volume), it is also important to consider the weight of the BBs used or the piston weight with regard to a possible Joule Creep effect. For optimal performance, the manufacturer recommends combining it with NBU AirsoftParts components. The manufacturer recommends this full cylinder for guns with inner barrels 400 mm long or longer, such as certain M16, DMR AR15, AUG or AK (AKM, AK-47, AK-74) configurations.
Why Is the Inner Surface of the Cylinder Polished?
The polished stainless steel surface provides a smooth, low-friction surface along which the sealing elements of the NBU piston head move during the operating cycle. Proper lubrication and seal condition are important for reliable operation of the entire air seal system.
| Variants | NBU (400+ mm) |
| Color | Silver |
| Body/receiver material | Metal |