I need help with guns?

So when you equip the gun i made the left and right arms look like they're holding a gun, however when the character walks the arms look funny and go in different directions and my friend mentioned something about a grip, so how do i use a "grip"?

For the weapon to work you must weld all the parts together.

Okay first off please show us the script. If I'm not mistaken I'm pretty sure what you should do is first is make sure none of the gun parts are anchored.Then what you do is check if the Tool grip position(which is a property) is fit to your needs. Not that the gun will be welded to one hand being the right hand. To make both hand hold this gun you should either use animations or a lookvector placed in side the left arm. A lookvector returns the facing direction to what ever position you choose.

Link here: "http://wiki.roblox.com/index.php?title=Lookvector#Properties"