In today’s Photo of the Day, we get a look at one of the Royal Navy’s .50 caliber FN M3M door guns in action. The photos were shared by 820 Naval Air Squadron, which is currently assigned to Britain’s new aircraft carriers – HMS Queen Elizabeth and HMS Prince of Wales.

A Lieutenant, likely the flight observer, mans an M3M mounted aboard an 820 Naval Air Squadron Merlin Mk2 (Royal Navy)

The FN’s M3M, also known as the GAU-21, has a rate of fire up to 1,100 RPM and a range of 2,000m. A development of the iconic M2 Browning, the gun has been in service with the US Navy, USMC and US Air Force for over a decade as well as with other nations around the world.

An M3M mounted aboard an 820 Naval Air Squadron Merlin Mk2 (Royal Navy)

These photos were taken during a training exercise at Royal Navy Air Station Culdrose, in southwest England. M3M seen here is mounted aboard a AgustaWestland Merlin Mk.2 which operates in an offensive support and anti-submarine role.

820 Naval Air Squadron also shared some video of the M3M in action:

Target practice! This week our crews have done some successful warfare training @RNASCuldrose including a series of M3M shoots. Essential skills to protect the carriers @HMSQNLZ and @HMSPWLS. Big thanks to our engineers for the work that goes into making it happen. pic.twitter.com/2B8RPv3Mck

— 820 Naval Air Squadron (@820NAS) July 30, 2020