What are the mechanics of the SD9VE?

[only2hands]

I do not know much about the mechanics of guns. Basically what I want to know is, on the SD and similar guns, once the slide is racked causing the striker to be cocked, is pulling the trigger the only way to release the striker? Is there any other way that the gun can go off without pulling the trigger? Do the mechanics ever fail causing an accidental discharge? For example, if my SD has one in the chamber can the gun be discharged say by dropping it on the ground? Or by a spring breaking? And what are the chances of this happening?

[a62rambler]

Originally Posted by only2hands

... is pulling the trigger the only way to release the striker? Is there any other way that the gun can go off without pulling the trigger? Do the mechanics ever fail causing an accidental discharge? For example, if my SD has one in the chamber can the gun be discharged say by dropping it on the ground? Or by a spring breaking? And what are the chances of this happening?

Yes. No. No. No. No. approximately 0.00000000000000000001%
The striker is cocked but it's forward travel is blocked by an internal safety that requires the trigger to release it to allow it to travel fully forward. The SD is capable of being dropped without releasing the striker. In theory it is possible for the internal safety to fail but even a broken spring would not allow it to release unless the trigger is pulled. If the spring was removed then you would have to invert the pistol and jar the block enough for it to move out of place. Then you'd have to somehow get the sear to disengage. The chances of the combination would be less than the likelihood a supermodel will like this post enough to fall in love with me and beg me to marry her. If that doesn't alleviate your concerns then I'll post a picture of this one legged old fat man and that should remove any doubt!

[cbr6864]

The SD does not cock the striker like Glock or XD with the SD the striker is only reset. Try this rack the slide back a fraction of an inch you will hear the striker reset. The SD has a heavy trigger compared to Glock and XD because you must fully pull back the striker with the trigger pull. The SD is very safe as the striker is not cocked back like other striker fired guns and on top of that there is the firing pin block. The only way to get an SD to fire without pulling the trigger is to have the firing pin block fail and drop the gun from an extreme height muzzle down and somehow create enough force to cause the striker to drive forward with enough force to set off the primer.

If your trigger/sear springs break all that will happen is a failure to reset.

Now the chances of that actually happening are about the same as finding an honest politician

[shawn mccarver]

Originally Posted by cbr6864

The SD does not cock the striker like Glock or XD with the SD the striker is only reset. Try this rack the slide back a fraction of an inch you will hear the striker reset. The SD has a heavy trigger compared to Glock and XD because you must fully pull back the striker with the trigger pull. The SD is very safe as the striker is not cocked back like other striker fired guns and on top of that there is the firing pin block. The only way to get an SD to fire without pulling the trigger is to have the firing pin block fail and drop the gun from an extreme height muzzle down and somehow create enough force to cause the striker to drive forward with enough force to set off the primer.

If your trigger/sear springs break all that will happen is a failure to reset.

Now the chances of that actually happening are about the same as finding an honest politician

I agree. One of the reasons the SIGMA and the SD trigger pulls are longer and heavier than the M&P and Glock is that the striker is basically NOT pre-cocked by the running of the slide. The Glock is partially pre-cocked (which is why it was originally classified as a DAO by the ATF), while the Springfield XD and the M&P are either at or nearly at full cock, as I understand it.

The firing pin safety prevents inertial discharge from a drop or jarring of the pistol to its front and the articulating trigger prevents inertial firing if the pistol is dropped on its rear (necessary because it is a striker fired action rather than hammer fired).

The SIGMA and SD Series pistols are every bit as safe as an S&W revolver, provided they have not been modified and are operating within spec.

[only2hands]

Thanks for the info. The other day I was in our LGS and hesitantly asked one of the young men behind the counter basically the same question that I asked here. He replied by saying that the function of racking the slide cocked the striker. He did not have an SD in stock, but grabbed an XD which has the visual striker indicator and said that all semi-autos cock the striker when racked. I asked him if the trigger had any function in cocking the striker in which he replied, "no". I did not feel that he knew for sure, so that is why I asked the question here. So thanks again for your info, I feel I understand my SD a lot better, and will feel more confident in carrying with one in the pipe. It's just a mental thing, as I can carry my revolver with one in the hole without hesitation.