What indicates that a single action revolver's hammer is cocked?

The indication that a single action revolver's hammer is cocked is represented by the raised hammer. In a single action revolver, the hammer must be manually cocked before firing; when this action occurs, the hammer is positioned in an elevated state. This positioning visually signifies that the revolver is ready to fire, as the hammer is in the correct position to strike the firing pin when the trigger is pulled.

The physical appearance of the raised hammer not only alerts the shooter that the revolver is cocked but also serves as a safety mechanism, as it prevents accidental discharge if the gun is not handled correctly. Therefore, the presence of the raised hammer is directly linked to the firearm's readiness to be fired in single action mode.

Chamber alignment, barrel attachment, and shutter lock do not provide the same direct indication of the hammer's position; while they are important aspects of a revolver's overall function and safety, they do not specifically signal whether the hammer is cocked.