If I were buying an economical single shot, and I will be soon. It would be a H&R Handi-Rifle. IMO they have a better feel and are better made than the Rossi. My personal choice is going to be 25-06. Easier on the shoulder than the .270 Win. Not that either are hard recoiling guns. I also wouldn't shy away from the .243. It's an awesome caliber that is usually reserved for the recoil sensitive, but just because you're a bit bigger than most women or children that doesn't make the bullet any less effective.

Physical size has nothing to do with the size caliber a hunter uses...I'm
6' 5", 250....Have used a .243 since 1980, killed at least 150 deer with, it works just fine....My brothers use the 7mm-08 and .270, they also work...
We see no difference in how far a deer travels after the shot with either a center lung shot or high shoulder shot....Each year we kill 40-50 deer on our 3 farms, spread that out over 25 years or so, it should give you a pretty good basis for comparison....

One thing my brothers have noticed is that I make better shot placements than they do, thus my deer either drop on the spot or within 50 yards.....

There are 4 advantages that I have noticed that come with using a rifle that is a light kicker....1) I use it year round, crows, coyotes, groundhogs, whatever, it's what I use...2) I never lose sight of the deer after the shot, I keep the scope on them, so I see the result 3) I can shoot from either shoulder, if a deer appears on my off shoulder, I flip the rifle over and take the shot, no need to stand up, turn around and get on the deer, which can easily spook them before the shot...4) Since I enjoy shooting, I practice more, making me a better shot, my brothers actually get me to sight in their rifles, because they don't enjoy shooting as much as I do....

On the "age" thing...I'm 52, guess I'm still too young to move up to a "big boys" gun...

Browning 300 WSM. I hateto lose wounded deer. With a BOSS on the barrel, it has no more recoil than a 243.

I would opt for either a 270 or a 7mm-08. If you are concerned about recoil look at the reduced recoil loads now offered by Remington and others. Once the shooter is proficient AND needs the option for longer shots, step them up to normal, full-power loads. If they will be shooting under 200 yards for deer and smaller game, just keep with the reduced recoil loads and you're done. Also, make sure you have a really good recoil pad on the rifle from the start and try to avoid a youth model as they are generally lighter and will kick harder. Plenty of eye releif for the scope too, don't want them to get bit. And don't make them shoot paper to start, put a plastic gallon milk jug out at 35 yards full of water (food dye red or green or blue for fun) and let them shoot those for a while. Make it fun and keep their minds off the recoil. Only shoot a few shells and then switch over to a .22 semi-auto and just have fun with it.

Good luck!

30-30 marlin lever action. You will have it the rest of your life.

mello