10 x.303 was an adequate - but no more - armament for air to air work when the design came out; the Hawker Typhoon began life with an 12 x .303 fit (the Mk Ia) before moving to the 4 x 20mm with which its associated today. The Air Staff, contrary to some myths, realised that aircraft armour would make the .303 unviable sooner rather than later, and was talking about fitting cannon into single seat fighters before the war began. The problem was the licence for the Hispano and establishing the manufacturing capability.If i stood in front of it the rounds would go over my head as it was a tail dragger, the whole analogy is stupid. German aircraft were increasingly immune to .303
or was the reason the RAF went to the .50 (Mk VIII onwards with E wings) and 20mm to make Stockholders in Hispano and Colt happy?