I took the plunge and ordered some. Not sure I need it but I have had some copper fouling with slow dirty powders and copper bullets like the 800 series of powders esp. the Milsurp.
TUBB Dust is an anti coppering powder that you can add to any powder supposedly. I am guessing it is bismuth or magnesium but could be other materials too. So in an effort to add more Fairy dust to my loads I will add the TUBB Dust as I couldn't find any Fairy dust online.
I know in most of my rifles I could just follow any dirty powder with one that already has an anti copper agent to help clean it up but that is not the same as adding the pixie dust to each load.
Link:
http://www.davidtubb.com/index.php?route=product/product&product_id=186Tubb is not only one of if not the best in his game he is also an all around good guy. The only one of his products I question are the speed firing pins but I have not tried them so don't know. The rest that I have tried do pretty much what he says they will.