We called them Super Smackers; they got outlawed after some shattered and or flew off the strings injuring kids that were nearby.
As far as ammo, I used to be able to buy 22LR at Howlands hardware in Plain City Ohio around 69. I was nine years old. Mr. Howland knew my dad and he had given his permission for me to buy them. They were around .50 a box. Ater school I would grab the .22 Marlin and go to the dump down behind the neighbor's house and shoot rats, tin cans crows etc. It was no big deal. If I saw a groundhog near the garden, he was toast.
We rode our bikes on the road without protective gear, climbed out the windows onto the roof to look at the stars, and played with fireworks. I didn't even know they were illegal.
Things are definitely different today. Some would say we have evolved, IMO we have devolved.