Congratulations. I think you will love the .280 Ackley. I had one built last summer and I love that thing too. Killed a nice cow elk with one shot at 450 yards last fall and a week later I got a 4 point whitetail buck with one shot also at 200 yards.
What scope you going with? I chose a 4.5-14x40mm Leupold with the B&C reticle. Seems to work pretty nicely and I like that power range. It is also the very first variable scope I have ever had on a rifle!
David