Well my post was in response to Roger saying Triple7 is the worst. Its hardly the worst. Pyrodex is far worse. I would go as far as to say its worse than some real black in terms of corrosion. Ive seen 3 sheets of steel that had all 3 burned on them and left in a garage for several days IIRC. After 4 days in a garage they were cleaned and the plate with Pyrodex had by far the worst pitting. The plate with Triple7 didn't look too bad at all.