[Kuramae Studio] APS-1 Grand Master BRASS Plated Cylinder

This is a custom cylinder exclusively for the APS-1 Grand Master series.
*This is a JASG certified part.
*If you choose to receive a free piston cup, please read this page carefully to the end and be sure to include the serial number in the remarks column.
*This product is intended for those who can disassemble and assemble the APS-1 themselves.

This is a custom cylinder made of brass with a chrome-plated brass machined cylinder head/cylinder end.
*The [APS-1 Grand Master BRASS Plated Cylinder] is a JASG certified part.
*When assembled into an APS-1 Mk.3, the initial velocity will be around 87 m/s.



Compared to the genuine unplated aluminum cylinder, both strength and durability are greatly improved.
The chrome plating reduces friction, preventing wear of the piston cup and greatly reducing dust generation, which can reduce the frequency of maintenance.

In addition, a drop in initial velocity due to the genuine cylinder has been observed in the early lots of the APS-1 Mk.3, and replacing it with this cylinder can fundamentally solve the problem.
*When used in the first lot of the APS-1 Mk.3, the piston cup must also be replaced with a new one at the same time.



Furthermore, friction between the cylinder and frame is reduced, allowing for very smooth cocking operation.
*The gun body is not included in the product.


・Adopts a nozzle-integrated, disassemblable cylinder head to reduce the possibility of air leaks.
It also contributes to increased rigidity of the nozzle.



・The cylinder end can be disassembled with two Phillips screws.
*When removing the piston, please remove it from the rear as much as possible.

・Set contents
Cylinder (brass with chrome plating)
Cylinder head (with O-ring / machined brass with chrome plating)
Cylinder end (with 2 fixing screws / machined brass with chrome plating)

*The piston / spring / spring guide use genuine parts.


Regarding installation on APS-1 Mk.3
In the first lot of APS-1 Mk.3, abnormal wear of the piston cup caused by the genuine cylinder has been confirmed, so the piston cup must also be replaced with a new one.
If you are installing this product on an APS-1 Mk.3 first lot, please order the piston cup set.


Precautions during maintenance
When disassembling the cylinder for maintenance and removing the piston, please remove it from the cylinder end side as much as possible.


When inserting the piston, please insert it from the front.



～How to distinguish between APS-1 Mk.3 first lot / second lot～

・APS-1 Mk.3 purchased before September 6, 2024, is the first lot.
・Units with serial numbers starting with MB166～ are first lot.
・If you remove the magazine rail, there is a brass insert on the main body side, and units with only one insert are first lot.



Customers who purchased an APS-1 Mk.3 first lot from our store will receive a new piston cup free of charge.
When ordering, please be sure to write the serial number of your APS-1 Mk.3 in the remarks column.
*Free provision is one piston cup per APS-1 Mk.3 purchased.