How to make gun sway script affect camera

So, I am trying to add my gun sway effect to my camera that draws my guns over everything else instead of adding the script to every gun, because if I do that my bullets just fly through the walls and that is a problem in the next phase of my game; targets. So, I am really frustrated with this, so please, if anyone knows what I should do, please post your answer down below.

Here are some links for you.