I created a new post to make my question at bit more clear.
Im using CSS models for my swep and i changed the material. It works fine, i can see the material in-game. The problem just is that it did not only change the material for my swep it also changed the material for the same weapon in the CSS weapons pack, because it´s a CSS weapon im using.
How can i make it so it only changes my material and not the whole weapon in general.