You would think these companies like Hornady and Federal would understand the value of providing components in order to hasten widespread use of their new
vundercartouches.
But they don't.
Federal utterly refuses to sell .338 Fed unprimed brass to the "handloading trade", though the underlings there do recognize they're screwing the pooch by not catering to the people most likely to adopt and promote their cartridge -- handloaders.
Wonder how long it will be before you can buy .338 RCM brass?
At least with the .338 Fed it's a simple pass of .308 brass through a .338 Fed die.
Nice adaptive solution to your dilemna. No you can't have any of my .356 Win brass
.
DN