A muzzle exit tester system comprises a barrel having an input end and an exit end, a shock plunger freely movable within the barrel, and a shock plate having a first side that faces the exit end of the barrel. A support isolation structure resiliently supports the shock plate, and receives a portion of the barrel that includes the exit end of the barrel. A pneumatic shock apparatus is operatively coupled to the input end of the barrel. The pneumatic shock apparatus is configured to retract the plunger in the barrel via a vacuum while producing a gas pressure charge, and subsequently release the gas pressure charge, such that the plunger accelerates to the exit end of the barrel and impacts the shock plate. The shock plate is configured to resonate at frequencies and amplitudes corresponding to a shock condition of a gun muzzle exit when impacted by the plunger.