| Airsoft, like any other sport, involves many scientific | | | | pellets because of their high stability, but sniper |
| principles that go relatively unnoticed. In the heat of | | | | weights can reach as high as .43g (although very |
| battle, one rarely worries about something like the | | | | expensive upgrades are required to use this grade of |
| transfer of kinetic energy. While knowing airsoft | | | | pellet). The heaviest pellet is .88g, which is never |
| physics will not realistically help you in a game, the | | | | used in airsoft because it is incredibly slow, not to |
| principles are good to know. Knowledge of pellet | | | | mention very dangerous, as it is usually made of |
| ballistics, on the other hand, can help you with your | | | | steel. |
| game. | | | | Pellet velocity is determined primarily by the tension |
| Pellets transfer very small amounts of kinetic energy | | | | of the spring being used to propel the pellet, or in the |
| mainly because of their size. The transfer of energy | | | | case of gas airsoft guns, the type of gas being used. |
| is basically the power of impact. Airsoft and paintball | | | | Energy transfer is relative to the speed of the pellet, |
| energy transfers have been compared, and paintball | | | | and speed is also heavily affected by weight. For |
| transfers substantially more energy. Energy transfers | | | | example, a .12g pellet using .800J (the common |
| are measured in joules, the SI derived unit of energy. | | | | energy rate of airsoft) of energy will initially travel |
| A standard .20g BB traveling at 300ft/s transfers .8 | | | | 375fps. However, a .20g pellet utilizing the same |
| joules, while a standard paintball traveling at the same | | | | amount of energy only travels about 280fps, and a |
| speed transfers almost 12 joules. Energy transfer can | | | | .45g pellet will travel at about 200fps. For a .45g pellet |
| actually be calculated using a mathematical formula; E | | | | to reach the velocity of a 375fps .12g pellet, it would |
| = 1/2mv2, where E is joules, m is mass in kilograms, | | | | need to utilize more than 2.50J of energy. |
| and v is velocity in meters per second. Since paintballs | | | | Bernoulli's principle is the method through which pellets |
| transfer more kinetic energy, they could be | | | | fly. It is, interestingly, also the principle through which |
| considered more damaging than airsoft pellets. | | | | airplanes attain lift. Bernoulli's principle states that the |
| The weight of airsoft pellets significantly affects their | | | | velocities of fluids increase with a decrease in |
| speed and trajectory. The lighter a pellet is, the | | | | pressure. In relation to airsoft, there is a fluid (air) |
| faster it will travel, but it will also be less accurate | | | | above the pellet at a relatively high velocity, which |
| due to the fact it will be more susceptible to | | | | means the pressure above the airsoft pellet is lower |
| environmental factors like wind. Heavier pellets have | | | | than the pressure under it, as there is a smaller |
| straighter trajectories, so they are favorable to | | | | amount of air flowing under the pellet as there is |
| lighter pellets, but in many cases heavier pellets | | | | above it. Therefore, the pressure under the airsoft |
| cannot be used because the airsoft gun utilizing them | | | | pellet pushes up and lifts the pellet, allowing it to fly |
| is not strong enough to propel the pellets at a fast | | | | for a long period of time. Hop-up systems in airsoft |
| rate. Therefore, players that wish to use pellets | | | | guns apply backspin to pellets, making air travel |
| heavier than .25g usually need to upgrade their gun. | | | | faster along the top of the pellet and creating a |
| Another benefit of heavy pellets is that they | | | | larger difference in pressure between the top and |
| decelerate slowly, unlike light pellets, which start fast | | | | bottom. |
| but quickly lose speed. Airsoft snipers usually use .30g | | | | |