All the balls were air cooled. I thought that they were a bit hard when I was cutting off the sprue. I cut a few with some diagonal pliers and then found out that they twisted off cleaner without cutting them.
I will try the sandpaper trick on a few and see how they work. Might cast another 75 or more this week. I will also weigh a few of them and see how consistant they cast.
The Jeff Tanner mould really worked out nice.