This is without a doubt one of the most controversial cartridges and the Peak Alloy case has stymied most of the reloaders, but listening to Federal on this, the case doesn't have a tendency to stretch, so you really only need to resize the neck, and they do it on a Rock Chucker with a modified RCBS die. My guess is they ream an existing die into 7mm Backcountry, but I don't know for certain. There's a thread on the Shockshell 308 which uses a hybrid case, however, this Federal guy states that they have other cartridges in the works.
