It seems like the greatest contributing factor to the accidental discharges when the pistol is dropped is the actual weight of the trigger (the part). The inertia causes the trigger to continue to the rear far enough to cause the pistol to discharge when dropped onto a hard surface at a 30 degree angle, where the slide and the beavertail of the grip module are impacted nearly at the same time. Apparently no standard testing includes dropping pistols at this angle. This appears to be a flaw in the testing protocols. Some Sig P320's don't have the curved trigger and they are of lighter weight. These models with the lighter weight trigger part don't seem to be subject to this malady. The military M-17, although similar to the P320, isn't exactly the same and apparently isn't subject to this problem. Sig's "voluntary upgrade" will involve sending the complete firearm back to Sig for a replacement of the trigger and a modification of the grip module. The bad part of all of this is that there are claims that Sig has known for a very long time (at least a year) that the P320 with curved triggers were subject to this. I don't know if any of those rumors have been actually proven though. It wouldn't surprise me, because many other firearm manufacturers in the past, including Glock have denied problems with their products. This has worked in the past, but with today's rapid information highway, it may not work for Sig. Time will tell. More than likely, as P320 owners get back their guns with the "voluntary upgrades" and the passage of time, this will blow over.
