This book just passes as average or an OK guide.
If you are after exact dimensions & quality drawings dont buy this book.The author will have you trying to fit a 1/4 inch dowel into a .22cal bore to align washers, wipes etc.(page 61)
The bulk of the designs in this book are for small bore cans that wont last more than a full clip from a .22cal pistol.
The book is written with a 50:50 signal to noise ratio , it does have some good ideas,constrction material & general info on how to build your own disposable or quality reusable suppressors ,unfortunately you have to wade through a lot of carp to get it.
If you listened at school or have any sort of technical or practicle experience with firearms & basic engineering practices you could probably do better with another book on cans.
Basic design & construction of cans is freely available on the net , in text's .pdf's or at the US patent office , the latter is a place even the author suggests you check out for information.