This might help you a bit, here's archive with all my Hk416 references, a lot of good photos there: http://www.mediafire.com/?wmm0b99j587zfll As far as your model goes, your vertical grip needs to be shorter and thicker and your magazine is all wrong at this point. Iron sights could use a bit more attention too, there are…
Follow your refs better. 1. Top back end of the Upper, you're missing the Charging Handle. 2. Top rails are the wrong shape, same for the ones on the hand guard. 3. Edges on the bottom of the magwell need to be more rounded. It also has a slight incline to it, it is not parallel to the ground. 4. Back of the Upper and the…