I got the first number from one of my books (all my other books gleefully inform me that it has 4 .303s and 4 Hispano 20mm cannon, but don't say anything about the ammunition) and found a site on the internet with thos numbers as well, but they looked to be copied verbatum from the book I have, so I disregarded that as a source.
The source for the 2nd, lower ammount of ammunition was WarBirds 2.77.
BTW, If I had the book here, I'd have posted its title, author and publisher, but I am at work. (Things are FUBARed here today)
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We few, we happy few, we band of brothers;
For he to-day that sheds his blood with me
Shall be my brother
Bring the Spitfire F.MkXIVc to Aces High!!!
Sisu
-Karnak