from The Century Dictionary and Cyclopedia
- n. The spring in a gun-lock which causes the sear to catch in the notch of the tumbler. See cut under gun-lock.
Sorry, no etymologies found.
Now the sear-spring, then the sear-pin, the sear; now then, the bridle-screw and here the bridle-hammer; next the tumbler-pin, the trigger, and finally the tumbler; this is the tumbler.
You see, he said, first you remove the plunger-spring with this spring-hooklike this; then comes the screw of the sear-spring, you only unscrew that half way, then knock the sear-spring like this so that the pin here comes out of the hole; now you take the screw out entirely.