*If backordered, it may take 3-4 business days to 2 weeks.
The ultimate inner barrel that satisfies SPARK custom engineers
"Hiei®", a high-quality, ultra-precision inner barrel purely made in Japan, was developed with SPARK's concept and the cutting-edge metal processing technology of "da Vinci" craftsmen, who also created the custom barrel "Guren / Raizen" series, to achieve stable trajectories and groupings. Further improvements were made to various parts, resulting in the birth of "Hiei® Kai", the ultimate refined inner barrel.
It is made from the highest quality pure domestic stainless steel produced by cold forging, and also precision-processed by a high-precision CNC machine, also made in Japan.
To achieve stable HOP, the HOP window shape and polishing are meticulously crafted, and the end of the barrel features an ultra-long tapered process of 20 mm, designed so that a layer of air envelops the BB bullet!
The unconventional long taper straightens the air layer surrounding the BB bullet, and combined with the 6.05 mm tight diameter, it improves muzzle velocity, accuracy, and range.
For this Tokyo Marui gas blowback rifle, to pursue HOP stability, we dared to adopt an "Accuracy Bridge" structure, which differs from genuine or general-purpose products.
To prevent the potential clash with the loading nozzle, we spared no expense and implemented a craftsman's tapered process on the inner wall.
This is a high-quality, pure domestic product that brings together the best of Japanese technology, recommended for those seeking an even higher level of accuracy.
The airsoft gun inner barrel "Hiei" is a registered trademark of SPARK.
*Due to the special taper, the inner barrel cannot be cut.
*Power changes with installation. Please ensure that the power does not exceed the legal standard value (less than 0.989 J / 35°C), and adjust carefully, especially with heavy ammunition.
*Aftermarket packing is not recommended as it is prone to bridge interference.
[Size Lineup]
140mm / 180mm / 210mm / 250mm
Tokyo Marui: M4 / AKM / Type 89 GBBR compatible shape.
Not compatible with MP7 GBB.
Also compatible with DE Airsoft NOVESKE N4 series and Salvo Precision MCX series.
VFC: MCMR, etc.
*The position of the fixing groove for VFC varies depending on the lot, so please refer to the product images.
*Not compatible with HK416A5 V3.
Combined with SPARK's "Nekonade HOP" part, it achieves the best results, especially with the 250mm size.
When installing Nekonade HOP into the chamber of Tokyo Marui M4 series gas blowback rifles, cut both ends to a length of approximately 4.3mm before use.
Nekonade HOP cannot be used with MP7, AKM, Type 89, or VFC genuine products.
Due to the special taper, the inner barrel cannot be cut.
Power changes with installation. Please ensure that the power does not exceed the legal standard value (less than 0.989 J / 35°C), and adjust carefully, especially with heavy ammunition, at the user's responsibility.
Installation目安
- 140mm: For short barrel models around 5.5 inches
- 180mm: For M4 short barrel custom.
- 210mm: For genuine MWS, compatible with legal muzzle velocity.
(Confirmed in June 2022 lot)
- 250mm: NPAS adjustment required, focus on accuracy.
Even for lengths stated to be compatible with legal muzzle velocity, power may vary depending on part settings and individual differences. Therefore, please conduct inspections and customize within the legal muzzle velocity at the user's responsibility.
[Features of Hiei® Kai]
- Ultra-polished HOP window
Stable trajectory requires stable "hop-up".
Craftsmen thoroughly polish the inner wall, including the area around the HOP window, to eliminate uncertain factors affecting BBs.
The HOP window is subjected to "round cutting processing," which is extremely difficult to process, allowing the HOP packing to move smoothly and maximize its performance.
Extremely hard cold-forged stainless steel is very difficult to process due to its hardness, requiring a high-precision CNC machine, selection of cutting tools by skilled craftsmen, and precise programming for processing. The unconventional 20mm ultra-long taper suppresses rapid changes in resistance and increases in turbulence coefficient around the barrel exit, eliminating negative effects on accuracy. This maximizes the inherent accuracy of the gun.
- Pride in being Made in Japan
The meticulous round cutting of the HOP window, the polishing of the barrel's inner surface, and the long taper at the muzzle end are easy to describe in words, but creating an ultra-precise inner barrel from difficult-to-process cold-forged stainless steel requires high technical skill.
"Hiei® Kai" is a MADE IN JAPAN product that Japan is proud of to the world.
- Adoption of Accuracy Bridge shape
Standard GBB inner barrels typically have an indented top surface where they contact the HOP packing to avoid collision with the loading nozzle, but this caused HOP instability. Hiei® Kai, like electric guns, intentionally adopts a bridge structure to stabilize the HOP packing's movement, successfully achieving significantly uniform HOP application.
Of course, to prevent collision with the loading nozzle, the part where the nozzle enters is finished with a craftsman's tapered process, achieving a unique quality that cannot be replicated by machine finishing.
[Precautions]
- This product is for ages 18 and over, so individuals under 18 cannot purchase it.
- Even new products may have scratches on the main unit and accessories from the factory. Also, even with the same product, there may be individual differences in color, etc., but all are product specifications.
- Specifications of the exterior and configuration of accessories may change without notice. Also, products may be delivered in a revised or repackaged original box if the package is missing or damaged.
- When installing, please use a chronometer, etc., to ensure that the power does not violate legal limits.
- Processing and adjustments may be necessary during installation.
- The description of this product does not guarantee improved performance.
