The QF 25-pdr is the result of studies to replace both the field gun Ordnance QF 18 pounderhowitzer and 4.5 inch QF 4.5, which had been the main British field artillery pieces during the First World War. Mk 2 version look Mk1, also had a charge “Super” in a different cartridge. An additional charge to the Super charge was introduced in 1942 to increase the initial rate for anti-tank fire. Thereafter, the additional load was used with loads 2 and 3 shots with significant increases. The use of Super increased load necessitated the addition of a muzzle brake.