I too was raised playing War with neighbor kids, although I always borrowed toy guns, or used sticks because my father would not allow any toy weapons. I fired my first round at 5, and had my 'own' guns by 10. I did know the difference, and the 4 rules were literally beat into me until I could recite them from memory before I was allowed to hunt.
I have not been so harsh with my sons, they both were eager to learn the rules before they could shoot. My younger boy, who's 7, had to learn "Be sure of your target and beyond" the hard way, costing me a rear window in my Bronco, and him the ability to sit for a while, as well as being sidelined from shooting for a month.
But he is very careful now, and knows even a BBgun can do damage. My boys are out in the yard 'playing Army' as I type this; what's great is that they are working together, defeating a common, invisible, enemy. (Usually the Germans in Stalingrad, they've seen 'Enemy at the Gates' one too many times, I fear.) They use sticks, as I am also strict on toy guns; heck my 11 year old has a collection of real ones some of you guys might envy!
He also claims about half of mine, because he can shoot them well.
(It's genetic, ask my Dad!
)
They are never too young to learn the Four Rules. Start them early, make it fun, and stress safety. Then, sit back and watch them become riflemen and women.
I also made my 11 year old memorize the Rifleman's Prayer before he could fire my milsurps.
This is my rifle.
There are many like it, but this one is MINE.
My rifle is my best friend. It is my life.
I must master it as I must master my life.
My rifle without me is useless. Without my rifle, I am useless.
I must fire my rifle true.
I must shoot straighter than my enemy who is trying to kill me.
I must shoot him before he shoots me. I will...
My rifle and myself know that what counts in war is not the rounds we fire,
the noise of our bursts, nor the smoke we make.
We know it is the hits that count. We will hit...
My rifle is human, even as I, because it is my life.
Thus, I will learn it as a brother.
I will learn its weaknesses, its strengths, its parts, its accessories, its sights, and its barrel.
I will ever guard it against the ravages of weather and damage.
I will keep my rifle clean and ready, even as I am clean and ready.
We will become part of each other. We will...
Before God I swear this creed.
My rifle and myself are the defenders of my country.
We are the masters of our enemy.
We are the saviors of my life.
So be it, until there is no enemy, but PEACE.
BTW, he wants to become a Green Beret.