The Evolution of the ICS Upper: From the Classic Version to the MXP System
001
002
The ICS upper has evolved significantly over time. The earliest versions were very simple: the tappet plate was installed directly, along with the spring, cylinder, piston, and nozzle assembly, and then everything was joined with the lower. It was a functional and straightforward system, designed to be assembled and used without unnecessary complexity.
In those early versions, the forward assist button served a role very similar to the M4 system: it helped relieve stress on the gears, reducing tension and preventing the spring from working in an unfavorable position during the cycle.
The old version
The classic ICS version is defined by its simple design and traditional assembly logic. It had no major mechanical complexity, making the system easy to understand and maintain.
In short:
- simple assembly;
- classic tappet plate;
- spring, piston, and nozzle assembly inserted directly;
- final connection with the lower.
The new MXP version
The new MXP version takes things further. It now includes a more advanced system with blowback and a moving dust cover. The charging mechanism has also changed: when pulled, the system opens like a real AR15.
This change is not just cosmetic. The shape of the upper has been modified to support this new functionality, meaning the geometry is no longer the same as the previous version.
Additionally, this version includes an extra spring to enable the blowback function and the movement of the upper assembly.
Key differences
Classic ICS
- Simpler design
- More direct loading and operation
- No blowback
- Traditional internal assembly
001
ICS MXP
- More advanced system
- Functional blowback
- Moving dust cover
- Real AR15-style opening
- Additional spring to support the system
002
Compatibility and models
Fortunately, there are models available for both versions: both the older ICS and the new MXP. This allows you to maintain proper functionality and correct fit without compromising the logic of each system.
Conclusion
The evolution of the ICS upper shows the transition from a simple and functional system to a more advanced and realistic one. The older version focused on practicality, while the MXP introduces more mechanical realism and additional moving parts.
For that reason, it’s important to choose the correct version: even if they look similar, the old and new versions are not the same, and each requires its own dedicated kit.