I got my new copy of "The Fouling Shot" yesterday. A very interesting article by Ken Mollohan titled "Technical Ramblings: Modern Lubricants".
Of special interest is his experience using Dextron AFT for sprue plate lubricant. He got some in the mold cavities and it appeared to help casting.
I recommend that you visit the Cast Bullet Association and read the article.
It will be interesting to see feedback on this.