Now you have changed the subject then haven't you?
You went from "no minor should ever have anything but a BB gun" to
assuming we want our kid to have an AR. That being said, I am sure out
west where it is relatively safe to shoot one, there are teenagers
with ARs. They would usually start with a .22rf and demonstrate that
they are safe and knowledgable first but there are plenty of people
out in flyover country who understand a gun is a tool.
How have I changed the subject? My point was that you really can't
compare what was common 50 years ago to today. AR-15s had not been
invented that I know of and I don't think a teenager could run down
to the local gun store back then and buy a rifle designed for the
military back then.
I guess you never went to Ye Olde Hunter in Alexandria. They
specialized in old military rifles. Granted most were bolt action
because that was what most militaries had but you could also buy an M1
carbine with 20 and 30 round magazines if you had the money or any
number of SA pistols, pretty cheap. I was 19 when I bought my 34
Barretta for $40 and I walked out the door with it. Same with a .38
super 1911.