I'm of the bolt-action opinion for the young guys too. Ten to fifteen years ago when I was at this landmark in my life, my parents agreed to go in on my first rifle. A Marlin 981T, a tube fed bolt action. I loved that gun, but I was tall for my age so for the couple years it didn't fit me, I shot off the shooting bench or prone. Bolt actions are the great mix between fun and safe to a youngster. Plan on two stocks like a few have mentioned already, and you'll be in good shape. I also stand behind making your grandson learn to really shoot with iron sights first. It's a good skill to learn, as it (to me) is the basis for general marksmanship. Good luck and make sure you keep as .22 ammo around as possible! If he's anything like I was, he'll appreciate it!