Late 1970s while attending college and for several years after, I sold guns, ammo and all the stuff that goes along with them. Over that time many people came in the store with a firearm of some type to sell, buy ammo send in for repair etc., etc. With a handgun it typically went like this, they walked up to me as I was behind the gun showcases and pulled out the gun from a bag or pocket. Some pointed it at me or someone else. I grabbed at the gun, so it was pointed away. I always asked if it was unloaded, it always was, but 3 times when I checked. The gun had a live round in the chamber. These were all semi auto guns. Another fool stood standing at a showcase that at handgun ammo on the wall behind the counter looking for ammo. As I walked over to assist him. He pulled out a .25 cal pocket gun and leaned over the showcase asking about ammo for the gun and fired it into the sacks of ammo. No ammo was hit, I grabbed that gun away from the fool. It had an empty mag. The store owner ran over and after learning no one was shot, escorted the fool with his empty gun to go somewhere else to buy ammo. It was clearly an accident, the guy was shaking and apologizing.
Firearms safety never ends.