Hey Unobtanium, I will take a picture of the receiver where the barrel extensions sits once I get home later this evening. From my memory, that area seemed more or less "flawless" but I am more than happy to provide. Thanks for checking!
Thanks ede2301 for your reply. It does seem strange to me since the "lines" are completely straight and uniform. Apologies for the unclear picture because you can't really even make out the lines unless their is light shining on it and from a specific angle, hence the unclear pictures. Will try to take a better one when I get home but I agree it is cosmetic and shouldn't effect the performance at all.