Your life is hanging by a hair trigger that goes off with a feather touch.
Move back now until you face the door, and don't forget my pistol is within an inch of your ear, and this is a hair trigger.
Yet his nerves were still unstable and every impulse was on a hair trigger, so to speak.
Of course, the boys are as sore as boils over the way they keep on losing, and their tempers are on a hair trigger.
Quick firing depends more on the alert finger than on the hair trigger.
This does not have a hair trigger after the slack is taken up?
This tends to have the hair trigger as soon as you move it after the slack is taken up.
The hair trigger release may be operated either by hand, by a cord, or by a pneumatic device.
Again he proved the edge of his flint, set his hair trigger, and again and again it failed him.
They do not know that trigger-pull can vary from a hair trigger up to many pounds weight.