If you dare to say that certain weapons should not be allowed or that there are some places where they are not a good idea or there are some people who shouldn't have guns, you are automatically a "gun banner." It's as simple as that.
If you're in favor of banning any guns, you are a gun banner. Just because you don't want to ban all guns, it doesn't make you any less of a gun banner. There are no degrees of gun bannerism. You either are or you aren't. If you want to ban "assault weapons", you are a gun banner. If you want to ban .50 caliber rifles, you are a gun banner. If you want to ban guns that are painted pink, you are a gun banner.
It really is as simple as that.