Muzzle Velocity

Muzzle velocity refers to the speed at which a projectile (in the case of airsoft, a BB) leaves the barrel of the gun at the moment of firing. It is usually measured in meters per second (m/s) or feet per second (FPS). At many airsoft events, velocity limits are now measured based on the weight of the BBs used, as this significantly affects the energy in Joules. Some guns (DMRs, sniper rifles) can also take advantage of Joule Creep due to piston load, achieving higher energy outputs with heavier BBs. The listed muzzle velocity when buying a new replica is only indicative and refers to the speed using 0.20g BBs (which is the unwritten standard/default weight for testing). The muzzle velocity depends on the spring strength, air pressure (for gas and HPA systems), barrel length and diameter, air seal quality, and BB weight.

Units

m/s (meters per second): standard metric unit commonly used in Europe
FPS (feet per second): more commonly used in English-speaking countries (1 m/s ≈ 3.28 FPS)

Typical muzzle velocity values in airsoft

AEP pistols: 55–70 m/s
Gas GBB pistols: 85–110 m/s (GNB versions may reach 130+ m/s)
CO2 GBB pistols: 100–130 m/s (GNB versions and revolvers up to 150+ m/s)
AEG assault rifles, SMGs, and LMGs: 100–130 m/s
GBB assault rifles: 110–140 m/s
DMRs / sniper rifles: 130–160+ m/s

These values often vary depending on the field rules, where specific muzzle velocity limits are set for player safety.

How is it measured?

Muzzle velocity is measured using a chronograph – a device that records the speed of a BB as it passes between two sensors. The measurement is done with a specific BB weight, usually 0.20 g, to allow standardized comparison.

Related term – energy in Joules

Muzzle velocity directly affects the muzzle energy, which is expressed in Joules (J). It is calculated using the formula:

E = (m × v²) / 2, where m is the mass of the BB (in kilograms) and v is the muzzle velocity (in m/s).

Example: a 0.20 g BB traveling at 100 m/s has an energy of 1 Joule.

Practical importance

Muzzle velocity is one of the key parameters for tuning replicas and verifying compliance with field limits. Exceeding those limits may lead to disqualification or mandatory designation as a DMR/sniper with semi-auto only restrictions.