The book arrived yesterday, its 250 pages including the index.
A few things its not. It is not a detailed history of individual Birmingham gunmakers, nor is it a book which covers the mechanics of shotguns or their inventors patents. Rather it is a treatise about the the gun trade in Birmingham through various periods in time, with individual gunmakers being mentioned as examples, in places. It does have a large listing at the back of the book of 2346 gunmakers in Birmingham and a further 428 ancillary tradesmen operating in the Black Country. This list has been complied - somewhat painstakingly I would imagine - from a number of journals, directories and parish archives. It covers the period from 1660 to 1960.
The author worked at the Birmingham Central Library for about 30 years and this shows in his writing as the book is very thoroughly researched. There is much information in the book that will not be found elsewhere. This includes a number of tables showing how many gunmaking firms were in Birmingham at various times and details of locations.
When I get a new reference book I always read the bibliography and references at the back of the book, as these can lead to the location of original source research materiel. These are listed and show where some of the tables come from, which in some cases are PhD dissertations, written in the 1950's and 1960's.
On page 108 there is a table showing the number of gunmaker plants in Birmingham in 1949 and the number of workers in various bands, 1-9, 10-24 and so on. In the final column for the 4 firms employing over 200 people the table gives the total number of workers as 84. This is a typo and the figure is 2209. The figure 84 is in fact a percentage,meaning that in 1949 of the gunmking firms in Birmingham 84% worked for one of the big 4 firms. Although not named these would have to be, Webley & Scott, WW Greener, BSA, and Parker Hale. There is a caveat to this mentioned in the book and that is a lot of very small operations employing only a handful of men are not included. I am trying to get a copy of the dissertation that these statistics came from to get a better handle on it.
So if you are interested in the British gun trade as an entity I would recommend this book.