Comments by "Ray Purchase" (@raypurchase801) on "Why did Spitfires change their guns? (Ft. Jonathan Ferguson)" video.

Britain was very class-orientated in 1939. The air ace Johnny Johnson was refused a commission in the 1930s because, despite being a graduate (unusual at that time), he was considered too working class because his father was a policeman. So Johnson joined the Volunteer Reserves instead. Things changed very quickly from 1940. Squadrons suffered horrific casualties. Dead officers could only be replaced by promoting skilled NCOs from the ranks. Colonial servicemen were contemptuous of the class system. Aussies, Kiwis, Canucks, South Africans promoted skilled aviators solely upon merit and nothing else.
5
@FelixstoweFoamForge Correct. All down to the threat. Shoot at an armoured bomber with .303s. You'll make lots of holes without killing it. Shoot at a fast-turning fighter with cannon. You'll be shooting far less rounds. Perhaps all of them will miss. Bader favoured .303s. He told his pilots, "Get as close as you can before opening fire. When you think you're much too close, get even closer".
1