Drop Safety Failures: The Mechanics Behind SIG P320

[YeeHaa]

The Problem

What’s happening in the P320 is a confluence of two separate occurrences:

• The impact moves the trigger shoe rearwards through its pre-travel pivot. What may feel basically like slack or play in the trigger actually serves an important mechanical function: it moves the striker block safety out of the way. The trigger is telling the gun, “Okay, the trigger is being pulled on purpose, so clear the plunger out of the way of the striker so it’s free to travel far enough to impact the primer.”

• The impact jars the internal components, tests the limits of the fit between chassis and slide, and the striker slips off the sear. Only because the striker plunger was also moved out of the way by the trigger’s limited-but-sufficient amount of travel does the striker fire forwards unimpeded and ignite the primer.


The Fix

Those upgrades include:

http://www.thetruthaboutguns.com/2017/08/jeremy-s/mechanics-behind-sig-p320-drop-safety-failures/

 

[georgel]

Yeah, there are some straight forward fixes for the problem. It was the denial of the problem that was the issue.

Was it Dallas PD that first banned the gun and then put them back in service after SIGs assurances? What did they end up doing?

 

[WeepingAngel]

It was the denial of the problem that was the issue.

Kinda curious who denied it? I saw the legalese about it passing all USG/LE drop tests it had undergone, etc (which it did - none of them dropped it on the back of the slide), but I didn't see an outright denial.

 

[georgel]

Well, it seemed SIG was quick to pull that card, apparently without investigating further. It was in response to the PD saying there was a problem. Did the PD reinstate the gun just because SIG said that?

 

[Catfish]

Sig's defensive stance was "It passes the standardized tests - what more do you want?"
It sounds like their engineers were working on a solution while their marketers were playing politics.

 

[Ikarus1]

Should've went with the Iver Johnson test: