Magazines were weighted with dummy rounds! -- We visit SIG SAUER's test lab to watch them drop test the P320 with the parts that are included in their voluntary upgrade. These include a reduced-mass trigger, sear, and striker as well as a trigger disconnect safety and a new sear cage. FYI, the M17 pistol being delivered to the Army -- the military version of the commercial P320 -- already has all of these upgrades *plus* a manual thumb safety.