The Sig Sauer P320, a polymer framed, striker-fired semiautomatic pistol has long been embroiled in controversy and lawsuits. Sig is a long-established venerable firm that makes popular firearms. Glock owns around 70% of the American police market, a market Sig would surely love to commandeer. Sig does have some portion of that market, including the military and federal law enforcement, but even that market penetration might be in danger.
The P320, lawsuits claim, can sometimes fire without the trigger being pulled, even while secured in a proper holster.
I’ve been following the controversy for several years, and have been generally willing to give Sig the benefit of the doubt. Some lawsuits have found for Sig, others against and Sig has maintained there is nothing wrong with their design and the unintended discharges must be the fault of the users who somehow pulled the trigger.
Not so with the case of Ceres, CA police officer Salin Chrim, a School Resource Officer carrying an issued P320 in a department issued holster. In this case, we know Off. Chrim did nothing to cause the discharge. The weapon was properly secured in her duty holster, and her hand was not in contact with the weapon. We know this because there is video:
Graphic: Ceres Police Department. Public Domain.
As Off. Chrim opened the door of her police vehicle, the weapon discharged, causing a passerby to immediately turn toward Chrim. Chrim suffered a non-life-threatening leg injury. No one else was injured and no property was apparently damaged.
That weapon was sent off to California authorities for examination, but coincidentally, the FBI has released its report on the P320.
The impetus for the report was a 2024 unintentional discharge in Michigan:
On July 31, 2024, a MSP [Michigan State Police] motor officer was standing in a squad area with other members when his department issued Sig Sauer M18 fired uncommanded. The firearm was reportedly secured in the department issued Alien Gear Rapid Force Level 3 holster at the time of firing. According to the MSP motor officer’s statement and the statements of others present, at no time was the trigger pressed intentionally or inadvertently. The MSP motor officer had objects in his hands at the time of the event, including keys.
Graphic: Sig X Post
The M18 is a larger version of the P320 mechanism. While the FBI conducted the evaluation of the pistol, An Alien Gear (holster) representative was present. Sig was invited to attend but declined. The FBI’s testing was exhaustive. The complete FBI report is available at the aforementioned link. It concluded, in part:
A reliable test could not be developed at the time of this document to test the effectiveness of the secondary sear notch. However, testing did indicate with movements representing those common to a law enforcement officer it is possible to render the Striker Safety Lock inoperable and ineffective at preventing the striker from impacting a chambered round if complete sear engagement is lost. It is important to note that the Striker Safety Lock, by design, is the last safety in line to prevent an unintended discharge as it is in place to protect against a secondary sear notch override.
While examination of the subject weapon did not independently provide evidence of an uncommanded discharge it does indicate that it may be possible if sear engagement is lost. The disabling of the striker safety lock through movement and friction creates a condition which merits further exploration to fully assess potential risk.
BRF recommends that MSP weigh the content of this report with the outcome of the internal investigation in making its final determination related to the Sig Sauer M18 as an issued firearm within the department.
In other words, the FBI, which was careful with its language, concluded the M18/P320 family can spontaneously discharge without any input from the user, and the involved law enforcement agency might want to take that into consideration. I’m sure the involved officer has already taken it into consideration.
Is this an inherent fault in striker-fired, polymer-framed handguns? Apparently not as no such issue has been identified with Glock’s mechanism, or the similar mechanisms of a variety of other manufacturers.
Worn or damaged parts can sometimes cause various failures in any firearm, causing unintentional discharges or failures to fire when the weapon is properly used. Sig’s issue is unintentional discharges can apparently happen when the weapon is secured in a proper holster, and now the FBI has confirmed it. This report is confined to a single handgun, but this is an independent report and this isn't the only incidence of uncommanded discharge.
On July 9, ICE discontinued use of the P320, and will be replacing them with Glock 19 pistols, like all Glocks a striker-fired design with no parallel history of accidental discharges.
Sig might want to take that into consideration.
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Mike McDaniel is a USAF veteran, classically trained musician, Japanese and European fencer, life-long athlete, firearm instructor, retired police officer and high school and college English teacher. He is a published author and blogger. His home blog is Stately McDaniel Manor.