@False1
Nah, that's just Primorge making ample use of his artistic licence :-P

@Baggins
So what's causing that effect I keep seeing a lot on PBR renders?

It's an effect I can see all over your gun render, while your Helmet render shows no signs of it.  The best way I can explain it is 'flash photography'.  Imagine you photographed that gun with a flash, and then cropped it so that the falloff of the flash cannot be seen.  Basically, it looks like your gun was shot and cropped in that fashion, but the helmet doesn't.  Hard to tell whether it's a shadow thing or not, but there's something odd going on with some renders I see, and I only ever see it on PBR renders.