Glock action

[LightningJoe]

When a Glock is ready to fire, is all the energy needed to set off the primer already stored in the gun?


With a "double-action only" gun, your trigger finger supplies the energy (by compressing a spring) needed to set off the primer. With a single-action automatic, that spring gets compressed by the recoil energy working the action. Traditional double-action has some of both.


Is a Glock like a single-action automatic in the sense that it won't fire unless the action has already compressed a spring? Or does the spring get compressed by the trigger pull?

 

[Dabull]

yes, provided you have chambered a round.

 

[JollyRoger]

Old single-action (for want of better terms) striker-fired pistols were usually cheap, and the action was used because it was simple and inexpensive relative to traditional hammer and sear lockwork. The action involved a striker or firing pin which would be cocked by action of the slide: the firing pin had a projection which would ride over the sear as the slide went back, and the would be stopped by the sear on return. As the slide ran forward the firing pin spring would compress, leaving a firing pin under spring pressure just waiting for the trigger to be pulled and the sear to release the firing pin.

The Glock uses a different system. When cocked, the striker or firing pin rests only slightly retracted from its released position, with a projection behind a drawbar connected to the trigger. As the trigger is pulled, the striker is pushed back against the spring, storing energy. At a certain point near the end of the trigger pull, the drawbar is pushed down in the mechanism, releasing the striker to go forward and fire the gun. The slide retracts and goes forward, putting the striker and drawbar back into firing position.

Glock probably has an animation on its site, showing how this works.

 

[JohnKSa]

When a Glock is ready to fire, is all the energy needed to set off the primer already stored in the gun?

The Glock action is partially pre-cocked by the action of the slide and the remaining compression of the firing pin/striker spring is done by the trigger stroke.

The firing pin/striker spring is compressed about halfway by the action of the slide which means that it contains about 25% of the amount of energy it would have when dropped by a trigger stroke to fire the gun. The trigger stroke finishes the compression and adds the other 75% of the energy required to pop the primer.

Below is a picture of a cutaway Glock showing the compression of the striker spring in the fired position, in the "pre-cocked" condition (compression effected by slide action) and with the trigger pulled, just before the striker falls.

The ruler isn't in exactly the same position for each shot. (Sorry about that.)