40 mm Mk 4 gun completes first at-sea firings

BAE Systems has completed first at-sea firings of its new 40 mm Mk 4 naval gun in waters north of Gothenburg, marking the culmination of the Mk 4 development programme. The trial firings were conducted from the 36.5-metre picket boat HMS Jägaren in the week beginning 29 October. Installation of the engineering development prototype on board had been completed the previous week.

Development of the private venture 40 mm Mk 4 mounting, the latest evolution of the Bofors 40 mm L/70 line, began in 2009 with the aim of providing small inshore patrol craft and offshore patrol vessels with a compact, lightweight, and affordable multirole weapon system.

The system has been designed to realise a 40% reduction in weight, volume, and price compared with the 40 mm Mk 3; BAE Systems believes the lower price point and reduced installation footprint will open up opportunities in the patrol craft market previously denied to heavier 40 mm turrets.

While the previous 40 mm Mk 3 system weighs about 3,700 kg, the new non-penetrating Mk 4 mounting has been substantially re-engineered so as to bring weight down to less than 2,300 kg without ammunition.