A sensor system for detecting jarring, acceleration or other application of force to a firearm, and/or movement of the firearm into an undesired orientation, which includes a sensor array mounted to a firearm. The sensor array detects the excessive acceleration and/or movement of the firearm into certain orientations and generates a sensor signal indicative of a fault condition. In response, a control system blocks or interrupts the firing sequence of the firearm to prevent inadvertent discharge of a round of ammunition by the firearm.