75mm

The Ordnance QF 75 mm, abbreviated to OQF 75 mm, was a British tank-gun of the Second World War. It was obtained by boring out the Ordnance QF 6 pounder ("6 pdr") 57-mm anti-tank gun to 75-mm, to give better performance against infantry targets in a similar fashion to the 75mm M3 gun fitted to the American Sherman tank. The QF came from "quick-firing", referring to the use of ammunition with the shell and propellant in a single cartridge. The gun was also sometimes known as ROQF from Royal Ordnance (the manufacturer) Quick-Firing.

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