Never been hunting...
 

I've never been hunting but my husband and some of his friends want to go soon...and they want me to go, too. :-3
My problem is, I want to be a veterinarian someday, and so a humane death for the animals is a huge deal to me (not saying it isn't for others).
My husband and I wanted to buy this air rifle for myself: Stoeger x50? I don't know if I'm allowed to post links, so I won't just yet.
But if I did get that rifle, what is the largest thing I'd be able to humanely kill? And where would I shoot an animal to kill it instantly?
I just keep having this nightmare that I get too weak of a gun and shoot something and it's still alive and in terrible pain. I wake up really upset.
I want to make sure that doesn't happen.
Thanks for any info you could give me.

My goal, every time I shoot, is to make a humane kill. I can't stand to see animals suffer. When I want to drop a deer instantly with a rifle, I'll wait for a clean shot and aim for the shoulder blade. The bullet striking the shoulder blade seems to transmit energy to the chest cavity and will stop the heart on impact. The deer drops like a sack of potatoes. If you hit a little high, you take out the spine and the effect is the same. However shot through the chest taking out the lungs or heart will generally only allow the deer to live for 5 or 10 seconds. However far they run in that time, is the distance you have to track them.

Most hunters take ethics in hunting very seriously
from before the shot to after,
part of such is practice, using the right firearm for the right type of hunting you plan on doing,

first question is why do you want to hunt?
people hunt for different reasons,
food,
population control,
animal management,
critter control,
air rifle is ok for small game, squirrel, rabbits,
even up to coyote with a well placed shot,
but dont recomend it,
air rifles have come a long way, but are not as accurate off the shelf as a good .22 rifle or .28 ga shotgun
you will injure more game with an air rifle than you would with a dedicated firearm.
you will not eliminate the possibility of injuring animals,
all you can do is minimize the chance of that happening through practice, appropriate firearm, and choice of shots.
in time chances are you will injure an animal,
you will feel bad,
but have to know yourself and know you took precautions to avoid that, and learn from your mistake to try to avoid it from happening again.