"Guns of the FBI" was written by retired FBI Special Agent Bill Vanderpool, who spent many years on the FBI Firearms Training Unit and has a perfect background to write a book on this subject. This is not really a typical reference book; it reads much more like a series of oral recollections. That put me off a bit at first (I love me some tabular data!), but by the end of the book I was thoroughly enjoying it.

Vanderpool covers the different guns used by the Bureau, of course, including the 1930s selection of .38 revolvers, Winchester 1907 SLRs, Colt Monitors, Thompsons, and Springfield match rifles. This transitions into the use of more modern arms including M16s and MP5s, and the development of a formal sniper rifle (turns out that a pump action Remington 760 with a 4x Redfield scope is not an ideal precision rifle...).

In addition to the guns themselves, Vanderpool spends a lot of time discussing the ammunition, holsters, and in particular the shooting standards and training practices used over time. He was in the FTU when the 1986 Miami shootout took place, and has an interesting first-hand perspective on the changes to firearms and doctrine that were instituted afterwards (in particular the 10mm automatic).

The book is about 340 pages, with that being 250 pages of main content and about 90 pages of appendices. I found it quite interesting and engaging, and a very good overall history of the FBI's armaments and how the Bureau understood and used those armaments. Price is $60 from the publisher (Gun Digest) or $44 on Amazon at the time of this writing:

https://amzn.to/38Un2WE

https://www.gundigeststore.com/product/guns-of-the-fbi-a-history-of-the-bureaus-firearms-and-training/