Greg Martin just from what I've read, about 15' tall and 6' wide but I have no proof of that.
This year bought 10 siberian c seedlngs from treetime.ca Going to plant 5 in the orchard, the other 5 will put in pots and come winter keep them in a grow tent in the basement with lot's of water, humidity and miracle grow, hoping to get at least 3' whips to plant the following spring.
We have 2 baily peaches grown from rootstock of failed attempts at grafted peach trees. Largest is about a 10' tall peach, "bush". No idea if we'll ever see fruit from any of them, but hey, gotta try, right?