FPS WELL MB03 120 m/s FPS spring

WELL MB03 120 m/s FPS spring has been calibrated on original sniper rifle. The material used is steel wire burnished and pre-hardened carbon steel with addition of silicon and chromium EN10270 / 2.   The spring has coils with variable pitch in the central area and in that in contact with the spring guide and undergoes a process of grinding the two ends which guarantees optimal performance in the compression phase.Dimensions: - length: 210 mm- outside diameter: 10,25 mm