So, my Chinese military SKS has this weird pattern of wear on the barrel, and barrel only..
To add to that, it’s only on 1 side, the other side is practically mint condition with exception of a few dings and such

Also, there is this weird discoloration (yellow/greenish color) on 2 out of 3 bloodgroves on the bayonet, anyone know what it is, and how to remove it?

Thanks