After installing a chair rail in my basement office (8 x 8) I began to notice a couple of the screw (not nail) heads popping back through the drywall quite noticeably. The only thing I can think of is that the drywall wasn't sitting tight to the studs after I screwed it in and now as I nail the rail up, it is pushing the drywall tight again and the screws are popping out. Could I be using too big a nail for the molding? I think I am using 2" 6d finish nails. Before I install a chair rail in the rest of my basement (1000 sq. ft.) I want to know if this is likely to happen throughout. Would I get better results if I use smaller nails attached with a finish nail gun? And how often should I nail the rail, every stud (16" centers)? I was really hoping to have a chair rail throughout with a darker color paint underneath to break up the monotnous walls, but I want to make sure I am not going to end up with screw pops all over. If worst comes to worst I can use a wallpaper border to separate the two wall colors instead of the rail, but I would rather not. Thanks everyone and sorry for the long post.