There are four basic rules of firearms safety. They interlock wonderfully, in that you have to violate multiple rules for someone to be injured. They are as follows, and in order.
#1 All firearms are always loaded.
It doesn't matter if you're sure that the gun is empty. It really doesn't matter if someone else told you that it's empty. Until you physically verify that the gun is empty, you have to consider it loaded and ready to fire.
#2 Do not point a firearm at anything you do not want to destroy.
In the event that the gun in your hand fires, whatever it is aimed at is going to be broken, injured, or killed. Be mindful of this and of where your muzzle is pointed. It is a habit that should become ingrained, and with safe practice will become second nature. In addition, be aware of where other muzzles around you are pointed, so that you're not what's being aimed at.
#3 Keep your finger off the trigger until you are ready to fire.
A modern gun that is not broken or malfunctioning will not fire unless and until the trigger is pulled completely to the rear. If your finger is not on the trigger, bullets will not leave the gun.
#4 Be sure of your target and what is beyond it.
You are responsible for every round that you fire. If you cannot clearly identify your target, do not fire. If you have any question about where your round will go if you miss or the round passes through the target, do not fire. Wait until you can fire safely, move to a safer position, or simply pass up the shot.
In addition to the Four Rules, there are two other important safety bits to consider.
Let It Go
The first is never attempt to catch a falling gun. There's a saying that "a falling gun is all trigger." Attempting to catch a dropped gun seems to almost always result in the trigger getting pulled and a round going off. Modern guns are tough, and built with safeties to handle moderate drops, so let it fall. The gun may be damaged, but the damage is likely to be minimal, and with a far lower bill than a gunshot wound.
Dress for Safety
The second additional consideration involves range attire. Keep in mind that hot pieces of metal are ejected from the rear of the gun each time you fire, and that they can bounce unpredictably before they hit the ground.
- Wear solid shoes with a closed toe and a minimal heel to prevent foot injuries or trips and slips.
- Eye and ear protection are mandatory, so don't wear anything that will prevent their use.
- Hats are an excellent way to protect your head and face from bouncing brass.
- And finally, wear a shirt with at least short sleeves and a crew-neck collar. Ladies, I know you want to look cute, and I do appreciate it, but a piece of hot brass to the cleavage will make your shooting experience sub-optimal. The same goes for the guys; I get the appeal of the tank top, but hot brass stings our chests as badly as it does the gals. Pass on the fashion in favor of safety.