I started shooting at 5 while being supervised and hunting at 8 while within an arms reach of my father and grandfather. My dad was much the same way with me. I had to recite all the gun safety rules and know all parts of a gun before I could shoot with it. I started out with single shots and by the time I was 12 I was using pump action and lever action guns. I started shooting semi auto pistols at 15. I killed my first squirrel at 8 and deer at 10. It's all about maturity not age. As others have said, I see lots of adults every night who shouldn't ever have guns. But there are plenty of 16 year olds I'd have no problem walking the woods alone hunting... I know I did when I was 16 and managed to be just fine. My dad also put a watermelon out at 25 yards and shot it with his 30-06. Seeing that think blow into a million pieces was a real eye opener...
