I have been reloading since 1972 and early on learned to check several loading manuals before trusting any one manual for a max load just for that reason. I have also deleted Hornady from reloading data I trust. The only data I use now is Nosler, Sierra and Hodgdon.
I started loading in 1972 also, we are old guys. One comment. I agree, always consult more than one manual. But a key legal point for safety.
ONLY the powder company who sells a product is required to file a federal safety data sheet about the powder that they create and sell. Companies that sell reloading manuals as just selling us their test results from their test guns at that time.
When you create a product, such as Dove soap to wash dishes, or Round-Up to kill weeds, or H110 powder, you must ensure the government that is safe when instructions are followed. As such there are certain hoops a powder company must go through to put the product on the market. Those legal hoops are what makes H110 powder safe to use, if you follow directions. No reloading manual, has that direct requirement. If they publish something that blows up guns, of course they can be sued, but name one case where that has been successful.
My point is we can choose what manuals we "like" and we all do. The most current manual out there is the Nosler manual, from 2023, I like it because it has the most current powders listed.
You mentioned Nolser, Sierra and Hodgen manuals. My point is only Hodgen makes powder, they would be your safest source of data, because if they make errors, they can be sued directly for putting a dangerous product on the market.
An example. Alliant has an online source of recipes for all of their powders, That is the safest place on the planet to find load data to start with and then create your own loads watching pressure data.
For example, if you go to the Alliant site and look at the 300 powder and the 500 SW, it only gives one load. That load is the safest source you will find.
If you prefer Power Pistol, they have a recipe too.
You get very different velocity all else being equal. But what you know is both of those recipes are going to be "safe". Both will be close to maximum loads.
And that is why the company that makes a powder, is the safest source of reloading data.
That said, once safety is satisfied, the various reloading manuals may tweak the recipes, However, they use different barrel lengths, test barrels and such that confuse the issue.
My point to any new reloader or when dealing with some new caliber, is to always start low and work up, but that the company that makes that powder is the source of the safest loads. It does not matter much if we are loading 38 or 357 or even 10mm. But when you get to to 454, 460 and 500 calibers, a little research would be worth the time.
My 2 cents.
