RE: Difference in reloading manuals
Alot of people try to live by the manuals. That will either get you bad performance in some situations or dangerous levels.
I have seen guys with flattened primers, extractor marks, and tell me its safe cause some manual has it in there. I just shake my head.
As Sierra says, a manual isn't the rule. Just a guide that shows one man got these results from one gun. It gives you a place to start and a place to start looking for trouble signs.
Every gun is going to be different. Every bullet is going to create different pressures and different velocities. But as a general rule, I use Nosler, Sierra, Lymans, and Speer interchangably. The places you got to be careful is with Scirrocos, failsafes, TBBC, and barnes. I use Barnes data for these.