I think a 9 year old could handle it and it is known for being a good deer round. My first deer was taken with a Marlin 336 in .35 remington, my grandfather, and father have also taken deer with this rifle. Its going to be a good bit of gun for a 9 year old.
I thought the recoil was very tolerable with Remington 200 grain Cor-locked rounds. More of a shove than a kick. It didn't deafen me when I shot the deer without hearing protection.
.30-30 is another great option.
I can't speak for how smooth the actions of the newer ones are. But on our old one you really have to cycle it with a bit of enthusiasm or else it doesn't feed easily. Our newer 336 .30-30 cycles much better after having taken it completely apart, cleaned it thoroughly and polished some parts a little bit.
These guns are built to last, I would not be afraid to by a used one if the action cycles well. These guns tend to work a little better after they have had some rounds put through them.
Last edited by alex0535; December 2, 2012 at 10:10 PM.