If anyone really wants to know the inside story on U-505, and a little about what it was like to be on a type9 uboat, i HIGHLY recommend this book:
http://www.savasbeatie.com/books/STEELBOATS_book.htm
Ive read it cover to cover, probably 4 times now
(im pathetic)
This extract is good reading:
http://www.uboatwaffe.net/books/books.cgi?a=4