VSR-10 100 m/s Spring – FPS

The FPS Softair 100 m/s spring is designed for bolt-action airsoft rifles based on the Tokyo Marui VSR-10 platform and compatible clones. Entirely manufactured in Italy, it is made from carbon steel alloyed with silicon and chromium, featuring variable-pitch coils and ground ends to promote consistent compression and long-term durability.

Features and technical specifications

• Manufacturer: FPS Softair
• Model: VSR100+
• Type: replacement spring for bolt-action airsoft rifles
• Claimed nominal velocity: 100 m/s
• Compatibility: Tokyo Marui VSR-10 and mechanically compatible clones, including WELL MB03 and CYMA M24 CM.702
• Material: burnished, pre-hardened carbon steel alloyed with silicon and chromium, manufactured to EN 10270-2 specifications
• Construction: variable-pitch coils in the central section and near the spring guide
• Ends: ground to optimise compression
• Heat treatment: oven stabilisation at 400°C for 30 minutes
• Length: 210 mm
• Outer diameter: 10.25 mm
• Manufacturing origin: 100% Made in Italy

Calibration and performance

FPS calibrated this spring using the original WELL MB03 mechanism as its reference configuration. Actual muzzle velocity may vary depending on barrel length and the mechanical characteristics of the airsoft replica.

The manufacturer's calibration does not account for the thickness of spring guide bearings. According to FPS, each additional bearing may increase muzzle velocity by approximately 2.5 m/s, assuming all other conditions remain unchanged.

After installation, the replica's actual power output must be checked using a chronograph.