Weird artifacts appeared in eevee because of normal map I'm was working on a shotgun and suddenly for some reason some weird artifacts appeared on the metal materials. 



I know that removing the image texture and leaving only a noise texture+bump on the normal input makes the artifacts disappear and also I don't see it when rendering in cycles: 



It was working with no problem before. I already tried copying the model to a new file and it didn't work.

the file:
http://pasteall.org/blend/index.php?id=51576
You should delete your UV Maps in the Object Data. Since you're not using UV Map based texturing.



Otherwise, you'll get unwanted UV Map data assigned to your mesh. 
Best to just delete them when they're not being used.



In your case, (as shown in the picture above) because you are not using UV Map based texturing for any part of your model; you should delete the UV Maps for all the parts of the model.