My Sako .308win loved the stuff and I used it exclusively. As a ball powder it metered well. I also used in a .223Rem, and again, no problems.
Does it burn dirty? Can't say I've ever really noticed as given a similar number of rounds, I always take about the same time to clean any of my rifles.
By burning dirty I mean soot on the cartridge case and in particular on its neck. I don't clean the barrels on well shooting rifles.
I am quite sure my memory is correct that we paid $.60 a pound for it. I would not take Ball C for free
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"Anyone seeking simplistic answers to very complex questions is showing his own inexperience - including what is meant by a "dirty" or "temperature sensitive" powder and how it affects things. It doesn't work that way."LOL