I love how most of the guys here act as if they can never be surprised by anything. Not!
Yes, well done. Intellectual property can be sub-divided into certain categories:
Industrial, which includes
Registered Design,
Patents and Trademarks
And copyright, which includes
Literary copyright
Musical/visual copyright
sound recording copyright
etc, you get the picture.
The gun designs would be a registered design, because it’s used for industry and manufacture. Which means you cannot make a gun that looks exactly the same without permission, or for anything else in the arms industry that looks exactly the same. However, models in a game mod comes under artistic copyright, because it’s creative rather than for industrial purposes. There is no copyright by the original designers on using those gun images in a computer game, it doesn’t fall within their domain. They only have the rights for using the image in arms manufacture. However, the actual creators of the models have put their time and effort into creating them, and thus the copyright for those models is theirs, not that of the original gun manufacturers. It’s like saying that Apple own the copyright for any gmod model that looks like an ipod. They don’t, they have no control over that whatsoever.
Understand?