I'm struggling to understand how two less in the magazine and poorer feeding with minimal velocity gain makes this new case a worthy choice over an 06-based round...
I think you're probably right (though I do like short actions).
Per my new issue of Rifleshooter, the 338RCM has the same case capacity as the 30-06, and the 300RCM being slightly longer sits half way between the 30-06 and 300WSM (ala 300 SAUM).
The article tries to make a case for improved short-barrel performance, and that may be the case with the tailored pressure curves Hornady ammo is providing, but of course handloaders are likely to be disappointed.
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