Winchester powders are now in the Hodgdon Powder Co. stable and this company provides all loads data from the powder manufacturer's end. No doubt, bullet companies will slowly catch up over the years as they rerun tests. Hodgdon provides information through two channels: its online menu-driven Reloading Data Center facility.
https://www.hodgdonreloading.com/reloading-data-center
............ and its printed 'Annual Manual', a once a year magazine type publication which you'd need to order through wherever you buy Hodgdon group powders. (Covers Hodgdon, IMR, Winchester, Ramshot, Accurate powders, but most grades are no longer available here thanks to REACH).
StaBALL 6.5 is very close indeed to Hodgdon H4350 in loads and performance, I did a side by side test between the two using a 6.5X55 F-Class rifle and 140gn match bullet here:
HANDLOADING BENCH REACH-OUT 10 – EU COMPLIANT POWDERS BY LAURIE HOLLAND
I liked the powder. The only performance downside I could find was that MVs failed to live up to Hodgdon's claims.
SB 6.5 will definitely meet your .30-06 application. 6.5-284 maybe too, or it might maybe be better with the slowest of the three StaBALL grades 'HD'.
For those with an interest in the StaBALL (alleged) Hodgdon VarGET replacement, StaBALL 'Match', I'll be range testing it against single-based tubular powder equivalents in 223 Rem and 308 Win, once the weather improves.
