Originally Posted by SpiritLifter
Well with a grey mare you have a single creme dilute with an Ee, Crcr. And of course, with a black sire, there is the Agouti A gene that when crossed with the dams' Ee, Crcr brings about a 50% chance of a brown according to the color calculator. That is unless the Agouti A gene is diluted of course when combined with the single creme dilute of the dam.
..huh? You are WAY off base here. The OP didn't say what the mare's original color is, just that she is gray, so where did you get the cream from? Gray is caused by the gray gene, not cream. Ee Crcr without agouti would be smoky black, but that's assuming there is no agouti.
Black also means there is NO agouti. Agouti is what turns black into bay, brown, or wild bay.
I have no idea what you put into that calculator to get brown and I'm pretty lost for where you got this information..