To render the firearm incapable of firing.
It depends on what you mean. Gun safety class for what purpose? Illinois does not issue a gun carry permit so there is no safety class for that. If you mean for a different purpose, it depends on what the purpose it.
Because if you are against gun safety, you're probably dangerous when handling a gun. Many people that are not for gun safety never will and don't know as much as they probably should know about their gun/guns they own.
What do you mean 500 feet used in gun safety?
Possible if the safety or the gun is damaged. Unlikely, but possible.
That is where the bullet comes out of the gun.
The purpose of a safety device is to reduce the danger of injury.
Rules for safe firearms handling and use are on gun safety tests.
That will vary with the purpose for which you have the gun.
The purpose of a paintball gun is to fire paintball pellets, to mark opponents in the game of paintball.
I would surmise, because they are ignorant of gun safety rules and/or totally unconcerned with the safety and welfare of their children - or they are mentally disturbed.
Weapon.
Anyone who has a firearm should take a gun handling and safety course. Guns don't shoot themselves.