We usually use Tapcons when mounting Dishes to brick. As an additional measure, we do put some clear silicone on the back of the mount and over the screw holes.
To be honest, its a much cleaner installation and if you ever had to remove the Dish since your not leaving 4 big holes in the brick.
If im not mistaken we use 5/16 x 1 5/8. It takes a 1/4 inch drill to put them in and a 5/16 hex bit to drive them into the brick.