.256 Winchester. Using data from my 1969 45th Edition LymanReloading handbook.View attachment 81521
Alliant's data shows a regular CCI 500 spp with the 2400 load data....https://www.alliantpowder.com/reloa...x?gtypeid=1&weight=158&shellid=28&bulletid=38
No prob. And just an FYI, if you go to their home page, and select products, and select a powder, you can see all of their loads broken out for that particular powder. It makes finding a load a bit easier.
As an example, here's all of their different 357mag loads for 2400..https://www.alliantpowder.com/reloaders/powderlist.aspx?type=1&powderid=9&cartridge=28.