Airsoft is a competitive team shooting sport in which participants tag and eliminate opposing players with spherical plastic projectiles launched via replica air weapons called airsoft guns.
Airsoft pellets do not typically leave markings on their target, and hits are not always visibly apparent. Though the pellets can sometimes leave red contusions or “welts” on exposed skin, the game relies heavily on an honor system in which the person who has been hit is ethically responsible for calling themselves out.
The airsoft guns used are typically magazine-fed, with some having manual spring charged systems similar to Nerf Blasters, or powered by replaceable compressed gas (e.g. propane, 1,1,1,2-tetrafluoroethane/”green gas” or CO2) canisters, or are battery-powered. Many airsoft guns also have mounting platforms compatible with genuine firearm accessories, and cosmetically more resembling to real guns. This makes them popular for military simulation and historical reenactments. There are also professional gun safety and weapon manipulation trainings conducted with airsoft in some fields, such as law enforcement, due to better safety and lower cost. The United States Coast Guard, for instance, has officially adopted airsoft for training in 2018.
Gameplay varies in style and composition, but often range from short-term skirmishes, organized scenarios, close quarters battle, field, military simulations (MilSim) or historical reenactments. They are played in indoor courses or outdoor fields. Combat situations on the battlefield may involve the use of military tactics to achieve objectives set in each game. Participants may attempt to emulate the tactical equipment and accessories used by modern military and police organizations. A game is normally kept safe by trained professionals.
Before gameplay, an airsoft gun’s muzzle velocity is usually checked through a chronograph and usually measured in feet per second (FPS). Some countries have a set velocity or kinetic energy restriction, guns shooting over the legal velocity can be confiscated. Some playing fields further restrict projectile velocity.
Airsoft originated from Japan in the early 1970s, trademarked as “soft air gun”, tailoring to the needs of shooting enthusiasts while conforming to Japan’s strict gun control. The name “soft air” referred to the compressed Freon-silicone oil mixture (later replaced by a propane-silicone oil mixture known as “Green Gas”) that was used as a propellant, which was significantly weaker than the carbon dioxide used in proper airguns (pellet guns and BB guns). Originally designed for target shooting, their plastic pellets can be shot at humans without causing injury and this became popular for casual wargames, which the Japanese called survival games (サバイバルゲーム sabaibaru gēmu). Airsoft guns spread to the UK in the late 1980s and early 1990s with a company called LS. The guns were sold in pieces and had to be assembled before they were capable of shooting pellets. Airsoft equipment was designed to closely emulate real guns. Since the mid-1980s, airsoft guns have been adapted with a purely recreational application in mind, and the sport is enjoyed by all ages. Airsoft replicas are produced globally, with the majority being manufactured in Asia. Many law enforcement agencies and military units within the United States now use Airsoft for force-on-force training drills.
On impact, the pain an airsoft pellet causes is directly related with the kinetic energy it has. This energy is directly proportional to its mass and the square of its velocity. It is important to note that doubling the velocity of a pellet will quadruple its kinetic energy. As a reference value, a 6 mm 0.20 gram pellet, which is the most common size and weight, traveling at 100 metres per second (330 ft/s) has one joule of kinetic energy.
Different regions vary in the velocity airsoft guns are allowed to shoot at. In the United States, velocity differs from the type of gameplay field. Close Quarter Battle arenas typically regulate velocity on airsoft guns at around 110 metres per second (350ft). For outdoor fields, velocity is usually regulated by the type of gun. Fully automatic Airsoft Electric Guns (AEGs) are often set at 120 metres per second (400 ft/s) and less, semi-automatic DMR-style AEGs at 120-140 metres per second (400-450ft/s), and 140-150 metres per second (450-500ft/s) for bolt-action sniper rifles. These are measured with a 0.20 gram pellet.
The maximum effective range of field-legal airsoft guns is all around 100 m (110 yd) with a highly upgraded sniper rifle replica. Most airsoft guns used for field play will have an effective range of around 43–67 m (47–73 yd), depending on the intended role of the equipment. Most Airsoft guns are capable of shooting from 60 m/s (200 ft/s) to 125 m/s (410 ft/s), although it is also possible to purchase upgraded internals for some Airsoft guns that will enable the gun to shoot up to 170 m/s (550 ft/s) or higher. In California a common limit for CQB is 110 m/s (350 ft/s). In Ireland, Italy, and Japan the energy limit for Airsoft guns is one joule regardless of the type of game play. Some UK sites allow semi-automatic-only equipment up to 88 m/s (290 ft/s) and bolt-action rifles up to 95 m/s (310 ft/s). However, the majority of UK sites allow both semi-automatic equipment and bolt-action rifles up to 107 m/s (350 ft/s). Northern Ireland has a maximum velocity of 100 m/s (330 ft/s) with 0.20 g pellets, without regard to the type of equipment. In Sweden the legal limitations of airsoft guns caps the energy limit at 10 joules for single fire guns and 3 joules for semi-automatic and fully automatic guns.
The ballistics of spring or electrically powered airsoft guns differ from real firearms in that a longer barrel will not always result in better accuracy. In spring/electric airsoft equipment, barrel length does not have a significant effect on accuracy. The “sweet spot” for barrel length in a spring/electric powered airsoft gun is around 450 mm. Past that length, added barrel length will not improve accuracy. In any case, barrel quality, velocity consistency, and hopup quality/design are more important factors with regard to accuracy. Added barrel length will result in slightly increased velocity if the cylinder size and compression are appropriate for the barrel length. For example, a gun with a large cylinder and a long barrel will shoot slightly harder than a gun with a small cylinder and a short barrel (ceteris paribus). This rule will apply even for barrels longer than 500 mm, if there is enough cylinder volume and air compression to propel the pellet through the barrel. However, the resulting velocity increase will be hardly noticeable. The only considerable advantage of using a longer inner barrel in an AEG or spring powered gun is that it generally will make the gun quieter.
Gas powered replicas function more like real firearms. In gas powered guns, added barrel length (to an appropriate degree) will result in significantly increased velocity, and increased accuracy to a degree. Tighter bore barrels will increase velocity because there will be less space between the pellet and the barrel for the air to escape through. Most stock airsoft guns have 6.05-6.08 mm bore barrels, but best performance is usually seen with “tightbore” barrels, which are 6.01 to 6.05 in diameter. However, the tighter the bore, the more likely the chance of a pellet jam, and subsequently, tight bores need to be cleaned regularly. It is generally agreed upon that a good quality 6.01-6.02 mm barrel will provide the highest muzzle velocity, while a good quality 6.03 mm or 6.05 mm barrel will provide the best compromise between power, accuracy, and ease of maintenance. The actual accuracy difference between tight bore sizes is debatable and usually outweighed by bore consistency.