@Nzfly is the man when it comes to these. This is just my opinion but I've seen quite a few different 416 upper receivers over the past year or so. None, even the PD beaters I bought had as much carbon built up at the crown of the barrel as your picture shows. Where the charging handle engages the upper reciever also looks heavily worn in similar fashion to my PD trade in uppers. However, all the PD trade in ones I've had and seen are marked with date codes and serial #s with proof markings. This would be nowhere near unfired and looks much more in line with heavily used PD trade in uppers.