How do I make it so that when you are carrying a gun or something and you turn very fast in a FPS game, the weapon will move to the side a little bit. Like in Half Life 2? Is there a good way to do this? I hope you understood my question. Thanks 
its very much understood, Just create an IPO (animtion) of it moving a little bit and when a key is press to turn then set it to play the IPO.
If you are looking for a certain speed you’ll need python to calculated rotation speed on a mesh. then you’ll find out what orinentation is ^_-
mabye slow parent i dont rember where the buttons are though