The problem is not information, friend, the problem is the amount of information that you can put between two covers and still carry the book.
Major E.G.B. Reynolds did a great book on the Lee-Enfield, back in 1960. It had a good chunk of information in it but it was definitely not complete. Ian Skennerton has done a couple of gigantic books on the same rifles.... and they are not complete, either. I own a couple of things that are not in either book, but that's not surprising when you start thinking about the time-frame involved. The British started experimenting with the Lee magazine rifle system in 1879 and there were still modernised versions in BRITISH Service more than a century later. India, Pakistan and many small countries still are using them in one role or another and those two countries are still manuacturing all the parts for the rifles, except for receivers. My old copy of Small Arms of the World lists 31 different versions of the Lee-Enfield rifle. A friend OWNS 36. I have 2 that even he doesn't have and I have seen half a dozen that neither of us have. And the Pattern Room, when I was there in 1976, had FOUR HUNDRED of them on its racks, ALL DIFFERENT: the results of a century of experimentation.
And it's just as bad with a whole bunch of others. Germany adopted their first Mauser in 1871 and they STILL have a few in Service, 140 years later....... but they sure aren't the same as the first ones!!!!! Several countries in South America still preserve quantities of century-old Mausers for ceremonial use.
It's just impossible to put it all into one book. You have several good suggestions here so far and I would suggest strongly that you start your own arms library (as most of us already have done). When you buy a rifle, buy a book also. Start with the more general books and the ones which answer the most questions. In this regard, the one I always recommend is "Hatcher's Notebook" by Major-General Julian S. Hatcher. Hatcher directed the US machine-gun shool before the First World War, he was the man who discovered (and solved) the problem which led to a million Springfields being scrapped, he single-handedly founded the science of forensic firearms identification AND he was in on every phase of the M-1917 and the M-1 Garand programs. To top that off, he was an inveterate experimenter and a wonderful lecturer. His book is 500 or so pages of closely-condensed information about firearms and it is completely authoritative. Know what is in that book and you are well on your way to becoming a REAL expert on what makes them tick, how they work, what they are made of..... and what you can get away with. Someone told me that it is back in print by Stackpole's in Harrisburg, Pennsylvania. There is also an older edition downloadable for free if you scoot on over to milsurps dot com and take out a (free) membership there. They have an entire LIBRARY that you can download. Good start, anyway.
Another really good idea is to hang around this forum a bit every day. Look at what has come up here just in the last couple of weeks: Lee-Enfields, unknown Mausers, brand-new condition (legal) 1914 Lugers, Krag-Jorgensons, Vergueiros, Arisakas, and all of them have been discussed to one extent or another. There are some VERY good people on this forum; you could use your time a great deal less profitably.
All you need now is a good SMLE!
And a ROSS (of course!).
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