You weren't using your Silent Scope rifle for Silent Scope were you?
It doesn't matter what gun you use with that one. It is just plain broken. The only way to get any type of response is to turn the brightness up to ridiculous and unpleasant levels.
I haven't actually used the latest mamedox (I don't think, as I haven't followed it in a long time, so I don't know what the latest version is), but gun support was definitely not very good at all when I last tried.