Generally speaking, gun companies do not press issues regarding their guns in a game unless you misrepresent their product. This is a result of their enjoyment of the free advertising they get as part of games. Large FPS franchises such as CoD have never licensed the use of real guns. In fact they claim fair use of those guns in their products with a decent legal argument, but no manufacturer has had an interest in testing it since pulling their guns from a game doesn’t serve their needs.