Originally Posted by themighty9mm
This was more of an availability purchase. I was using ramshot tac. But my stash of that is pretty much depleted. I was kinda caught with my pants down. At least as far as rifle powder goes. Picked up some aa2230 at a spot on price and in a quantity that would keep me shooting for a bit. Never really ran into such vastly different data in my manuals before. So it got me thinking about the current question. In the hornday manual 24 is max, in the lyman 24 is pretty much low mid range IIRC
You will always find a difference of opinion in reloading manuals. Sometimes it is because of slightly different components or different firearms. Certainly velocity will vary by firearm - my 20" .308 will always have less muzzle velocity than a 24" .308 for the same load.
My definitive answer for rifle reloading is the Sierra manual. I have decided that they do more actual testing than any other manufacturer and they are the ones I am going to use. Now, I have no factual basis for that decision, it's just the one I made.
Others use the Lyman manual and I think it's true that they have no entanglement with powder manufacturers. Speer is married to Alliant, for example, because they are owned by the same parent company.
I don't think you'll get in trouble using the Lyman manual - it is a published source of load data. I also think that most of the manufacturers have backed off on max loads over the years. I suspect that Lyman is perfectly acceptable. I would still look for primer flattening (even with Federal primers) or difficulty in extraction.
Or, I would use the lower value and keep the Lyman extra in mind in case I was worried about consistent powder drops.
I don't see the motivation for running anywhere near MAX. Unless you are trying to shoot way far out, velocity isn't a big deal. Consistency is more important.