For cleaning burn marks ( carbon ) from inside the cylinder Leadaway takes it out like butter . On a blued firearm it will remove the bluing , only on bare metal or stainless . For SS guns with burn marks on the face of the cylinder Leadaway removes it with no effort at all . Midway sells them .
PS: I shoot benchrest 308 and reload my own , Federal brass is thicked then most , are you only having this problem with Federal?
Chris