Guarder SP90 AEG Tune Up Spring

Reliable and excellently crafted spring from Guarder, made from oil-tempered and heat-treated SiCr spring steel. The nominal value of the spring strength 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 usually deviates less than 10% from the nominal value. Experience shows that the effective value is often higher than the nominal value, which is why in case of 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 tested. For systems with particularly good sealing (e.g., KWA G2X), significantly lower nominal values must be chosen.