A firearm safety device having a bolt for insertion through a trigger guard toward the lower receiver of the firearm. The bolt is inserted through the trigger guard so as to be positioned behind the trigger, in an axis generally perpendicular to the direction of pull of the trigger to prevent the trigger from be depressed and thus firing the weapon. The bolt extends from a base, which can be static in the form of a fixed bolt, or dynamic with the bolt configured for mechanized or electromechanical insertion through the trigger guard, such as by a lever operation, solenoid operation, or other operation. In one embodiment the safety device has a bolt affixed to a base, with the base configured to attach to the trigger guard. This embodiment provides a freely mobile transportable safety device. The safety device can be used with or integral with a firearm support mount, such as a gun rack. In this preferred with the bolt and/or base providing support beneath the firearm, while a front mount is provided to support the front of the lower receiver, or alternatively the stock or barrel of the firearm.