The Science of Airsoft

Airsoft, like any other sport, involves manyspeed. Airsoft snipers usually use .30g pellets
scientific principles that go relatively unnoticed. Inbecause of their high stability, but sniper weights
the heat of battle, one rarely worries aboutcan reach as high as .43g (although very
something like the transfer of kinetic energy.expensive upgrades are required to use this grade
While knowing airsoft physics will not realisticallyof pellet). The heaviest pellet is .88g, which is
help you in a game, the principles are good tonever used in airsoft because it is incredibly slow,
know. Knowledge of pellet ballistics, on the othernot to mention very dangerous, as it is usually
hand, can help you with your game.made of steel.
Pellets transfer very small amounts of kineticPellet velocity is determined primarily by the
energy mainly because of their size. The transfertension of the spring being used to propel the
of energy is basically the power of impact. Airsoftpellet, or in the case of gas airsoft guns, the type
and paintball energy transfers have beenof gas being used. Energy transfer is relative to
compared, and paintball transfers substantiallythe speed of the pellet, and speed is also heavily
more energy. Energy transfers are measured inaffected by weight. For example, a .12g pellet
joules, the SI derived unit of energy. A standardusing .800J (the common energy rate of airsoft)
.20g BB traveling at 300ft/s transfers .8 joules,of energy will initially travel 375fps. However, a
while a standard paintball traveling at the same.20g pellet utilizing the same amount of energy
speed transfers almost 12 joules. Energy transferonly travels about 280fps, and a .45g pellet will
can actually be calculated using a mathematicaltravel at about 200fps. For a .45g pellet to reach
formula; E = 1/2mv2, where E is joules, m isthe velocity of a 375fps .12g pellet, it would need
mass in kilograms, and v is velocity in meters perto utilize more than 2.50J of energy.
second. Since paintballs transfer more kineticBernoulli’s principle is the method through
energy, they could be considered more damagingwhich pellets fly. It is, interestingly, also the
than airsoft pellets.principle through which airplanes attain lift.
The weight of airsoft pellets significantly affectsBernoulli’s principle states that the velocities of
their speed and trajectory. The lighter a pellet is,fluids increase with a decrease in pressure. In
the faster it will travel, but it will also be lessrelation to airsoft, there is a fluid (air) above the
accurate due to the fact it will be morepellet at a relatively high velocity, which means
susceptible to environmental factors like wind.the pressure above the airsoft pellet is lower than
Heavier pellets have straighter trajectories, sothe pressure under it, as there is a smaller
they are favorable to lighter pellets, but in manyamount of air flowing under the pellet as there is
cases heavier pellets cannot be used because theabove it. Therefore, the pressure under the
airsoft gun utilizing them is not strong enough toairsoft pellet pushes up and lifts the pellet, allowing
propel the pellets at a fast rate. Therefore,it to fly for a long period of time. Hop-up systems
players that wish to use pellets heavier than .25gin airsoft guns apply backspin to pellets, making air
usually need to upgrade their gun. Another benefittravel faster along the top of the pellet and
of heavy pellets is that they decelerate slowly,creating a larger difference in pressure between
unlike light pellets, which start fast but quickly losethe top and bottom.