Gameplay varies in style and composition but often range from short-term skirmishes, organized scenarios, C.Q.B., field, military simulations (MilSim), or historical reenactments and indoor airsoft 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.
Airsoft originated in Japan, then spread to Hong Kong and China in the late 1970s. Airsoft guns spread to the UK in the 1980s with a company called LS. The guns were sold in pieces and had to be assembled before they were capable of firing 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. One of the first airsoft fields was Firefight Airsoft Games which was set up in 1996 in theUnited Kingdom, at Mapledurham Estate Reading. Airsoft replicas are produced globally, with the majority being manufactured in Asia. Many law enforcement agencies in the US use Airsoft for force-on-force training drills.http://www.amazon.com/Force-On-Force-Police-Training-Using-Airsoft/dp/1432726846
Ballistics and velocity
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 0.20 gram pellet traveling at 100 metres per second (330 ft/s) has one joule of kinetic energy.
A typical set of velocity for sanctioned fields in the United States on guns may be 120 metres per second (400 ft/s) for Close Quarters Battle (CQB), 140 metres per second (450 ft/s) for outdoor play with fully automatic AEG’s, 145 metres per second (475 ft/s) for semi-auto “DMR” style AEG’s, and 170 metres per second (550 ft/s) for bolt action sniper rifles, for a 0.20 g pellet.
The maximum effective range of field-legal airsoft weapons is around 90 m (98 yd) with a highly upgraded sniper rifle replica. Most airsoft guns used for field play will have an effective range of around 43–67 metres, depending on the intended role of the weapon.Most Airsoft guns are capable of shooting from 50 m/s (160 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 76 m (249 ft) to 90 m (300 ft) In California a common limit for CQB is 110 m/s (350 ft/s). Airsoft guns that have high muzzle velocities tend to have a longer range and better accuracy. On the other hand, a lower muzzle velocity means that the pellet will glide more, which is a good thing for indoor skirmishes. Outside however, the wind may change its trajectory.
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 weapons up to 120 m/s (390 ft/s) and bolt action rifles up to 500 ft/s (150 m/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 weapon.
The ballistics of spring or electric powered airsoft guns differ from real firearms in that a longer barrel will not always result in better accuracy. In spring/electric airsoft weapons, 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 400–500 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 6.04 in diameter. However, the tighter the bore, the more likely the chance of a pellet jam, and subsequently, tightbores 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 barrel will provide the best compromise between power, accuracy, and ease of maintenance. The actual accuracy difference between a 6.01 mm barrel and a 6.03 mm barrel is debatable.
The minimum safe level of gear required to participate in most games includes a pair of Ballistic eye wear ANSI Z87.1 (impact-rated) goggles to protect participants’ eyes. Traditional prescription glasses and sunglasses, or goggles not designed specifically for use with airsoft or paintball marker, may break or shatter upon being struck causing injury to the eye. Airsoft guns are not to be confused with BB guns.
Community safety precautions
Rules such as a maximum muzzle velocity and engagement distance guidelines are used by different groups. Some organizations have created common safety rules and guidelines.
When not actively playing, some fields require “barrel bags”, also known as barrel “socks” or barrel “condoms”, to be placed over the muzzle of the gun. The magazine is usually removed as well, and the gun fired to clear the chamber. Most fields also require players to leave their guns set to the safety position when they are not shooting, a practice common when using real firearms. In certain countries, such as the Philippines, additional special rules have been adopted.
Reference: Wikipedia Airsoft