http://www.youtube.com/watch?feature=player_detailpage&v=Q9Fciegxl94#t=356s You should work on your lighting. Honestly it doesn't look like you lit it at all. Study this one for example.
I understand wanting to keep it authentic in terms of the materials in which case CODs famas is a bad example but I think it definitely needs more signs of wear on the plastic parts considering how worn the metal bits are. Deep scratches in the plastic, marks where its scuffed against other surfaces, maybe even some paint…