Weapon Readiness Conditions

From Wikipedia

Colonel Cooper favored the Colt M1911 and its variants. There are several conditions of readiness in which such a weapon can be carried. Cooper promulgated most of the following terms:

Condition Zero: A round chambered, full magazine in place, hammer cocked, safety off.
Condition One: A round chambered, full magazine in place, hammer cocked, safety on.
Condition Two: A round chambered, full magazine in place, hammer down.
Condition Three: Chamber empty, full magazine in place, hammer down.
Condition Four: Chamber empty, no magazine, hammer down.

Some of these configurations are safer than others (for instance, a single action pistol without a firing pin safety should never be carried in Condition 2), while others are quicker to fire the gun (Condition 1).

This firearm condition system can also be used to refer to other firearm actions, particularly when illustrating the differences between carry modes considered to be safe for various actions. For example, DA/SA weapons are designed to be carried in Condition 2, which is not safe for 1911s. The Glock and actions like it, with no cocking or external safety mechanisms, do not have a state like Condition 2 or 1. They are 4, 3, or 0. We should go over that fact in detail when we have our safety briefings.