half-cock

verb (used with object)

1. to set the hammer of (a firearm) at half cock.

noun

1. the position of the hammer of a firearm when held halfway between the firing and retracted positions by a mechanism so that it will not operate.

noun

1. on a single-action firearm, a halfway position in which the hammer can be set for safety; in this position the trigger is cocked by the hammer which cannot reach the primer to fire the weapon
2. go off at half-cock or go off half-cocked
   1. to fail as a result of inadequate preparation or premature starting
   2. to act or function prematurely