Masking one weapon as another...

I love playing with hacked weapons because they are a lot better then the standard ones. The problem is that I am sick and tired of people seeing the weapons and atomaticlly calling me a cheater. I could use the invisabilty hack but that just ruins the game for me and people can still see what weapon they got killed with in the message area of the game. I was wondering if it was possible to trick the game into thinking and showing everybody I am using a certain weapon when I am really using a hacked one. For example showing them I am using an mp4 rather then a p90 would solve this problem. I was thinking about how to do this and I figured the most logical solution would be to record the packet of a gun and find the bytes that are associated with the sound and look of a weapon and to just copy and change that with a hacked weapon. If this seems logical or if this is probably impossible please explain to me.