To that I would add Guns of the Royal Air Force by Graham F Wallace, one of the senior weapons staff in the Ministry of Aircraft Production. Among other things he covers why the RAF used .303 Browning's instead of .50 Browning's -- and why the British Browning is far more complicated than the real Browning. Think a cross between Colonel Blimp, Major Bloodnok and Gilbert and Sullivan with a big dash of 1835 thrown in.