Prometheus EG Inner Barrel

The 363mm length is a standard size typically used in M4 carbine-length rifles. While it is compatible with many Tokyo Marui, Matrix, and G&P platforms, you should measure your current inner barrel to ensure the length matches your outer barrel assembly.

A 6.03mm bore is considered a 'tight bore' barrel. It minimizes the gap between the BB and the barrel wall, which reduces air leakage, increases muzzle velocity consistency, and significantly improves your grouping accuracy at range.

Stainless steel is highly durable and resistant to corrosion, making it lower maintenance than brass barrels. However, you should still clean it periodically with a soft cloth and silicone oil to remove debris and ensure the polished interior remains smooth.

The precision crown at the muzzle end helps stabilize the airflow as the BB exits the barrel. This reduces turbulence, which helps the BB maintain a straighter flight path and improves overall shot consistency.

While not strictly required, it is highly recommended. Since you are already opening the rifle to install a high-precision barrel, upgrading your hop-up bucking at the same time ensures a perfect air seal and maximizes the performance gains from the new barrel.