Originally Posted by Chillyrabbit
Somewhat, Since I'm also pretty new to this correct me if I'm wrong.
You can change fps using different weight bb's but this is only strictly speaking FPS, not energy or anything like that.
First you should probably get age verified to get more access to the forums.
WRONG. study physics more.
mass x acceleration = force
FPS is not the issue on airsoft guns, it's irrelevant to safety. what matters is MUZZLE ENERGY.
muzzle energy is what causes injury. velocity is just a part of that calculation.
We use 400 fps with .2s as a guideline because it roughly calculates to 1.5 Joules of energy. The limit is 1.5 Joules. It does not mean that when your gun shoots a gajillion FPS with a .2 that you can put a 1kg projectile into it to make it shoot 400 fps and have it qualify for field use.
a .2 BB traveling at 400 fps is 1.48J
a .4 BB traveling at 282.96 fps is STILL 1.48 J
a .4 BB traveling at 400 fps 2.96 J
a .2 BB with 2.96 J of energy is traveling at 565.93 fps.
To properly maintain a safe level of muzzle energy, you must reduce the energy propelling the projectile. That means on an electric gun you use a less powerful spring. on a gas gun, you change the valving to release less gas.