Safety

The safety on a gun is mentioned in GURPS Tactical Shooting on page 8, seen on page 4 of the preview at http://www.warehouse23.com/media/SJG37-0134_preview.pdf
Condition Zero (Cocked and Unlocked): A round is
chambered, the hammer is cocked, and the safety is off.
The pistol is ready to fire.
Condition One (Cocked and Locked): As above, but the
safety is on – the pistol isn’t ready. The safety can be thumbed off with a Ready maneuver; a familiar user
(High-Tech, p. 80) or one with Lightning Fingers (p. 39) can do this as a free action. Safeties rarely fail mechanically, making this a safe way to carry – nevertheless, most military and police organizations don’t allow it.
Condition Two (Hammer Down): A round is chambered
and the hammer is lowered, with the safety off. A singleaction weapon cannot fire until the shooter thumb-cocks
the hammer (treat as thumbing a safety, above). Going
from Condition Zero into Two requires carefully squeezing
the trigger while lowering the hammer over a loaded
chamber; this requires a Guns (Pistol) roll, at +4 if done
two-handed. Failure results in a shot fired; an 18 means
you shot yourself (typically in the leg or abdomen)! As it
isn’t entirely error-proof, Condition Two is considered
unsafe by many, and only suitable for advanced users.
Condition Three (Unready): The chamber is empty, the
hammer is down, and the safety is off. Rack the slide to simultaneously chamber a round and cock the hammer.
This takes a Ready maneuver; a successful Fast-Draw (Pistol)
roll lets you ready it instantly (p. B194) by racking the
slide while drawing. Condition Three is the safest way to
carry the gun, and is popular with the police and military.
Readying can’t be done silently and normally requires both
hands; One-Hand Drills (p. 39) is useful.
Condition 4 relates to unloaded weapons, there is no description of a "condition 3.5" or similar involving a weapon which is loaded, with an empty chamber, with the safety ON, though.
Category:Technology