FWIW, I have the Lyman 49th Edition, as well as the Hornady 3rd, 9th and 10th Editions.  I found that most of Lyman's data is generally on line with others... but I have found major discrepancies too!  I use the Lyman for my cast bullet data, but for my standard 30-40, 30-06, 7.7x58, and most others, I stick with the Hornady.

Now there was a case recently when a gun (not a Krag) was destroyed and the shooter used Lyman data which turned out to be erroneous.  I bounced the data reported against my manuals and found the same error in my Lyman manual too!  (I can remember the specifics, but I seem to recall it was in a Garand, and the load published was way to high a charge... almost as if the numbers were reversed).  Ever since, I use Lyman data very cautiously and consider the Hornady 9th and 10th my loading bibles!