I know that Brophy's book had some statements in it that were later proved to be not correct. A B&S bolt is, as you say, incorrect.

There is no M1903 book that is totally correct. From a beginner standpoint, probably Bruce Canfield's 2004 book (not the 1989 ed.) is a good place to start. Most collectors buy several and are aware of the flaws in each. The only two that I would not recommend are Joe Poyer's and Jesse Harrison's books, until you are experienced enough to separate the wheat from the chaff. Brophy and Campbell are also recommended, but both have their limitations, as does Canfield's book.