Merlin crew prove they're nifty with a fifty as they open fire with their .50 cal machine gun

Royal Navy aircrew have been test-firing their .50 calibre heavy machine gun – a weapon that makes the Merlin Mk2 that extra bit more versatile.

While the helicopter's primary job is hunting submarines, the Merlin can also deliver warning shots, act as overwatch for boarding parties or destroy small craft threatening a task group.

These crew members are from 820 Naval Air Squadron, based out of RNAS Culdrose, and are currently deployed on Exercise Steadfast Defender off Norway with the HMS Prince of Wales carrier strike group.

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The powerful .50 cal, which is known as the L111A1 12.7mm Heavy Machine Gun (HMG) in British service, is an updated version of the Browning M2.

That weapon was brought into service in 1933, but is still recognised as one of the finest heavy machine guns ever developed.

The HMG is used by the Army too.

It provides integral close-range support from a ground-mounted tripod or fitted to a vehicle, using a variety of sighting systems.

The performance of the HMG has recently been enhanced with a new 'soft mount' which helps reduce felt recoil and improves accuracy, along with a quick-change barrel.