A weapon mounting system for a vehicle, such as a helicopter. The weapon mounting system illustratively includes a weapon cradle supporting a machine gun for pivoting movement about a generally horizontal elevational axis. A carriage supports the weapon cradle and is supported by a pintle for rotation about a generally vertical azimuth axis. An ejection collection device is supported by the carriage and collects spent shell casings and links ejected from the machine gun for discharge through the pintle. A trigger assembly illustratively provides for manual operation by a gunner and for remote electrical operation by a pilot.