Prometheus MS90 Non-Linear Spring

Excellently crafted spring in the usual outstanding Prometheus quality, with a non-linear design for optimal performance and durability. The nominal strength of the spring indicates the expected value in m/s (meters per second) with 0.20g heavy ammunition and can be multiplied by a factor of 3.28 to achieve the value in fps.

The stated nominal value is only a guideline; the effective firing power depends on the tuner's skills and the system's sealing. With correct installation, the effective value typically deviates by less than 10% from the nominal value. Experience shows that the effective value is usually higher than the nominal value, which is why, if in doubt, one should always lean towards the next weaker spring. To achieve the desired muzzle velocity as optimally as possible, various components and combinations (springs, piston head, cylinder head etc.) often need to be tried out. For systems with particularly good sealing (e.g. KWA G2X), significantly lower nominal values must be chosen.