Hi all,
you're looking for avery good book called "The Modern Pneumatic Airgun", by H. M. Buckley, with a foreword by G. V. Cardew.

It's a comprehensive look at the construction of a single shot rifle, from start to finish, with loads of engineering drawings.

It even tells you how to blue the barrel.

Unfortunately, it isn't available commercally but only from the author at about £35, IIRC.

You can contact him using the following details;

Howard Buckley,
MPA,
East Lodge,
Snaith Road,
East Cowick Goole,
East Yorkshire DN14 9DA