The SIG Sauer P320 pistol has been a topic of discussion in the firearms community, with concerns arising from reports of unintended discharges. While SIG Sauer has maintained that the pistol meets all industry safety standards, they did introduce a "Voluntary Upgrade Program" to address these issues. This is a look at the factors that led to this program, the mechanics behind the problem, and the response from various organizations.

The Drop-Fire Problem and Its Mechanics

The core of the issue, which has been recreated in various online videos, is that when the P320 is dropped at a specific angle—landing on the rear of the slide at a 30-degree angle to the bore axis on a hard surface like concrete—it may discharge. This is due to a combination of design factors. Unlike many other popular striker-fired pistols, such as the Glock or Smith & Wesson M&P, the P320 lacks an external trigger safety. Slow-motion videos of the drop tests have shown that the trigger can move to the rear upon impact.

The pistol's internal safety mechanism, the striker safety, is designed to prevent the firing pin from moving forward unless the trigger is pulled. However, under the right conditions of a drop, the force of the impact can cause the trigger to move just enough to disengage the striker safety, allowing the pistol to fire.

Law Enforcement and Military Responses

Reports of unintentional discharges have prompted some law enforcement agencies to take action. Dallas Police, for example, issued a recall of all their P320 pistols, while other departments, like the North Dakota Highway Patrol and Santa Barbara Police, removed the P320 from their approved pistol lists. One Connecticut police officer was shot in the leg when his P320 accidentally hit the ground and subsequently fired.

The U.S. military's M17 pistol, which is a P320 variant, has also been involved in incidents, leading at least one Air Force command to stop issuing the pistol while an investigation is underway. This is particularly notable as the M17 was chosen for the military's Modular Handgun System (MHS) over the Glock in early 2017.

The "Voluntary Upgrade Program"

In response to the safety concerns, SIG Sauer initiated a voluntary upgrade program for all civilian and law enforcement P320 pistols. The upgrade includes an "enhanced trigger" system with new components that reduce the overall weight of the trigger, sear, and striker. The intent of these changes is to prevent the trigger from moving far enough to the rear to cause a discharge if the pistol is dropped. SIG Sauer covers the cost of the upgrade and shipping for all P320 owners who participate.

Despite initiating this program, SIG Sauer has not referred to it as a "recall." The company maintains that the P320 met and exceeded all industry safety standards at the time of its manufacture and that no pistol is "totally drop-safe."

Key Differences and Considerations

The P320's design philosophy, particularly its lack of a trigger safety, has been a key point of discussion. During the U.S. Military's XM17 pistol trials, SIG Sauer touted one of the P320's advantages over the Glock was that the user didn’t need to pull the trigger to field-strip the pistol. Ultimately, however, the final M17 pistol selection simply came down to the lowest bidder.

The fact that the military-issued M17 pistols were not affected by the voluntary upgrade program is a crucial distinction. This is because the M17 was already being manufactured with the updated parts. The P320's situation highlights a broader debate within the firearms industry about the balance between technical solutions and user training. With approximately 500,000 P320s already in circulation, the voluntary upgrade program is a massive undertaking for SIG Sauer.