I would like to thank you
ALL for your excellent replies, which have given me a totally different (and more accurate) perspective of air combat and the factors affecting 'victory rates'.
I did forget that RAF aircrfat had rifle calibre m/c guns whilst the LW had cannon, sparking a long and bitter arguement in the RAF as to which way to go. As I understand it Tuck was pro cannon Bader against but - eventually (and AT LAST) - the RAF did instal cannon but after BoB was over.
Thank you all again,
weinace