But holy cow

That book is NOT just about the development of this weapons. It starts with WW1, goes through all german small arms development programms since WW1, describes the strategic rationale, offers some of the best statistics about the number of small arms produces, and then only goes very far in depth about the Mkb. 42 to post-war assault & battle rifles.
Overall, it is a complete book about german weapons development, which does not only focus on the technical part.
IMO, it is the best book written about that subject that you can find.
The book has got a whooping 532 pages and every page is worth reading.
The book has recently reviewed by Ian from Forgotten Weapons. It seems to be that in the english translation, the book is quite expensive.
I could buy the book in german for a relatively low price.
Overall I would call this book a must have for everybody who is into german World War-weaponry.