Problems such as bore erosion, which led to a short barrel life and loss of accuracy, meant the gun was less than satisfractory, and the faults could not be rectified in the subsequent Mk XII gun.
Problems such as bore erosion, which led to a short barrel life, and inconsistent cordite propellant burning which led to loss of accuracy, meant the gun was less than satisfractory. The faults could not be rectified in the subsequent Mk XII gun.