I just bought a .45/90 Rifle and found that some of the bullets that I cast 2 - 3 years ago had a gray coating. I don't know if it is oxidation or just crud. I felt that at the very least it would cause more residue in my barrel between shots and cleaned up the ogives with steel wool. It was a lot of dirty nasty work and I wonder if it was worth it. Anybody know what it was and if I did the right thing .