I know its not a rifle but this still looks the place to post this.
Just bought a second hand hatsan escort luxano. It came with two barrels, 26" and 28". The finish on both barrels is damaged as is the black finish on the receiver. The previous owner put some kind of cleaning solution on it and tarnished it. It was going for a song so I bought as the rest of the gun is in mint condition with virtually no use after he damaged it which was not too long after he bought it. Have any of you any experience in repairing this sort of damage? Looking for hints and tips and recommended products to use. Bought this as a hide gun so will tend to use the 26" so I am happy to go out with a rough barrel while I work on the 28" to perfect the repair prior to trying it on the 26". I will try to up load some pics of the damage ASAP so you can see for yourselves what has been done.