On Mon, Mar 01, 1999 at 06:39:17PM +0000, Bennett Todd wrote:
> 1999-03-01-01:21:03 Juergen Leising:
> > just for interest - can somebody please explain to me, what a "hair trigger"
> > is?
> In common usage, it describes something that's easy to set off, a delicate
> sensor, etc. In this instance, someone was using the phrase to claim that the
> mailing list is too sensitive to email bouncing, and ends up unsubscribing
> users for brief transient problems.
> Originally the term came from certain premium quality firearms, including
> target rifles and duelling pistols (and probably some other specialty arms),
> where a hair trigger was basically a second-level trigger.
> A trigger releases the hammer, allowing a strong spring to drive the hammer
> into some ignition mechanism and set off a firearm. For reliable and accurate
> operation, it's desireable to have a very strong main spring, so the hammer
> hits hard and fast. But with a very strong main spring, the pressure the
> hammer sear (the catch that the trigger holds up) applies against the trigger
> is very strong, which means the friction of the trigger rubbing across the
> hammer sear is very strong, which means that you have a stiff trigger pull
> --- you have to pull on the trigger really hard, against a resistance. And
> _that_ --- having a stiff trigger --- is bad for accuracy, since it forces
> you to strain to release the trigger, which can throw your point of aim off.
> The ideal accurate trigger has as close as possible to zero release pressure,
> so you can't really tell exactly when you're pressing hard enough to make it
> go off. To address this conflict, they came up with a gizmo called a hair
> trigger. The hammer is cocked by pulling it back, then the _trigger_ is cocked
> by pushing it forward; all that pulling the trigger back has to do is release
> a light-weight internal clockwork which in turn releases the hammer. Hair
> triggers may have been good for accuracy in ideal conditions, when used by
> experts, but they have acquired a reputation for causing accidents, since they
> are so easy to set off by accident.
> -Bennett
Hmmm, you sound like an American. I've never seen such a detailed
description of a silly idiom. I hope Juergen appreciates your effort.
--
Andrew Bell
