Thanks KT.
My plan is to let him have the first shot with the 22, and then get it sighted in for him. After that, I'll fire off a couple of the 20's to see what it feels like. Even then I'm sure I'll have him wearing a heavy winter coat, regardless of the temps. The last thing I want is for him to be afraid of the gun.
By the way (bragging time

), I took him with me 2 weeks ago when I shot my new Springfield XD9 Pistol. He had never fired a gun other than my Ruger 10-22 before, but he took to the pistol like duck to water. I had him shooting at about 10 ft and he blew the heck out of the bullseye.

Think he's hooked.