I started off with a .308 and I was 5" nothing and might have weighed 100 pounds.
Depending the the make and model, the recoil is consedirably less than a .270. Most of the youngsters I started hunting with used a .243 or .308 (pretty much the same case size, just different caliber).
Those that shot .270's seemed to have flinchin issues.
The 25-06 is often sold short, but it's a super deer round. I still hunt with a .308 every once in a while. I've also killed deer with all the above mentioned rounds.
Depending on his size, I'd suggest the following along with where and how you hunt.
.243 or (6 mm)
.308
.25-06
.270
If you're hunting in an area where you better put the smack down on him or risk someone else trying to take your animal b/c it ran, rule out the .243 Average distance ran on a well placed double lung shot will be around 40-50 yards.
.308 - If you shoot some souped up loads supporting something like a 165 grain balistic tip, they rarely run very far if at all. Probably 80% of the deer I've shot with this caliber fell over dead on their feet and never took another step. You'll find more selection on .30 caliber bullets than any other out there. One more reason I give it (or any 30) a thumbs up!
.25-06 - Bullet selection isn't the greatest, but this gun puts them down just as good if not better than the .308. It's super charged and got some distance to it. If you're hunting in the midwest where you may be shooting more than 100 yards, I'd give this my first choice. Mostly use mine to shoot groundhogs out past 500 yards.
.270 - Now we're getting into personal preference. Although I've killed plenty of game with this round it's just not my personal choice of caliber. Not that it doesn't do the job, but if I were buying a new gun and the 4 calibers above were lined up, the .270 wouldn't be a consideration. That being said, I'm not bashing it and a lot of people use it and it's proven itself as a super deer round. I just don't think it's the proper choice for a youngster. Bullet selection isn't super, and there's so many other calibers out there with compariable or better balistics and energy that do have great bullet selection.
Now you .270 lovers, it's not a bash..just personal preference! ha ha
