[DonVoigt]

Tom is correct, in fact we can't agree on what book to start with.
Though the first luger books were way better than no references, they just did not get it all correct- which of course is to be expected- as we still learn every month, if not every day.

Lugers at Random was published in 1969 and while does have some good, basic info; it is also full of errors ; I would not waste my money on it today(I have owned my copy for decades). The problem is you don't know what is correct and what is erroneous! JMHO.

Kenyon identifies your DWM/BKIW produced U suffix luger as an "unmarked Simson rework", which it is not.

If you diligently search this forum and the other luger forum, you will have more, and better info- plus the opportunity to ask questions of many of the guys who actually wrote the later luger reference books.

Searching and reading for yourself is a requirement, as when one starts into any new area- we don't even know what questions to ask.

Don't trust much what is found online and in Wikipedia!