Weapons

I have couple of questions on weapon and pickups coding;
1)How do u use custom SKINS on pickups, the same mesh but different skin texture
2)How do you make guns fire different projectiles than they should, like the CAT gun.
3)Is it possible to put textures and classes in the same package
1)How do u use custom SKINS on pickups, the same mesh but different skin texture
2)How do you make guns fire different projectiles than they should, like the CAT gun.
3)Is it possible to put textures and classes in the same package