Use an expanding bullet of your choice, keep impact speed at 1800 FPS or greater, kill shit. It really is that simple, no need for all the mental gymnastics.
Energy is irrelevant, pick a bullet you want and then pick a cartridge that will meet the velocity requirements for expansion at your maximum intended range.
Until about 5 years ago everything I had was used. Learned alot and had a great time. It's less painful to learn the hard way if your initial expense is low. I always learn the hard way, MOA Leopolds/Vortex, Savage, buying 4x fired brass ect.
The company that I work for is headquartered in Israel. I think that the average American would be blown away by the patriotism of the Israeli people. FAFO is about to be stepped up to 9, maybe 9.5
I'm of the opinion that many teenagers need to learn the hard way, my son certainly did. He quit being quite as reckless once he realized that I wasn't going to pay for his mistakes. Broken fishing poles, crashed bicycles, fender benders ect. He payed his own way through hard work as a teenager...