Just starting to load 6.5 Creedmoor and none of my books even list it..Looking for recommendations for new manuals with 6.5 in them...My newest is a Sierra maybe 5 yyrs old and no 6.5.
That Sierra Manual is based on data only collected through 2002. It's ancient, compared to current manuals. ...And the data predates the cartridge, entirely.
The current Hornady manual has a good amount of data.
In addition to those listed above, the new Accurate full manual (488 page book) has the 6.5 Creedmoor, and the newer Hodgdon annuals also have data. Plus most powder and bullet manufacturers will list data online, particularly for newer cartridges.
Hornday X is good - its one of my two go to books. It has a number of powers and it has a range of all bullet types you can find that can be used to cross over to other mfg bullets (with caution, start low and work up)
I believe in paper manuals but I also cross-check new loads on-line. Seems like all major bullet makers as well as most powder mfgs have their data on line now. Speer bullets just started posting their data too.
I do look on line, but having the hard manuals is my go to day in and day out.
I particularity like Sierra (dated as it is) and Hornday as they list a larger number of powders that shot decently as opposed to a powder mfg that lists all their powders that work but not any more than that.
Sierra bad Hornady have such a wide bullet choice for each type you can (being careful to start low of course) extrapolate to other mgs.
A 5 years old manual was compiled and all the data tested about 7 to 8 years ago. Takes about 2 years or more to do that. Hornady didn't 'invent' the Creedmoor until 2008. Then there's the time it takes for shooters to accept a brand new unknown cartridge. After Hornady's marketing Department did their thing. The Creedmoor supposedly was first on the Hornady #9 manual published in 2013 too.
Anyway, there's 6.5 Creedmoor data on Hodgdon's site.
Any bullet maker's book(like Sierra) will have data for their products only. However, you do not need bullet specific data.
I would say, no matter what loading books you get/use, buy one of these Loadbooks. https://www.midwayusa.com/product/189111/loadbooks-usa-65-creedmoor-reloading-manual These caliber specific books contain most of the loading receipts that are available for the caliber from both powder and bullet manufacturers. BTW, they look like they were published with using a copy machine (but they are cheap), but the information is golden.. The books are updated as needed. The current 6.5 Creedmoor was last upgraded 2016.
Loading manuals are updated quite often making older ones obsolete to some extent. I finally quit buying them and use the ones by the powder companies and bullet manufacturers.