A great factory load is the Federal Premium with a 100 gr. Nosler Partition. Very accurate out of my Model 70 XTR Featherweight. Taken White-tail deer and feral hogs. The partition will drive thru at about any angle without a problem.

If you're going to reload your own any of the 95-100 gr. bullets are suitable for deer. My 10 year old daughter shoots this rifle with the partition load without a problem so your Grandson should do well! Good luck and great hunting.