I have a colt m4 .223 and i am new to the weapon.... First thing i wanted to learn is how to unload the gun safely.... i bought some dummy bullets to practice with ... ..understanding the mechanics of the gun is interesting ....to make the bullet eject i noticed that the charger unit has to be pulled back. at first it did not eject the bullet... after trying a few times i accidently let it snap closed.. i pulled it back and then the bullet ejected. could someone explain the mechanics of the ejection system.... does it need to snap over the bullet to eject it