I like the idea of the 6.5 Grendel or 6.8 SPC in Bull-Pup config....
Both good rounds. The ballistic coefficient on the 6.5 is incredible. Still supersonic at 600 meters! Only possible problem is linking for a MG. Think we’re probably at a point where some sort of disposable 200 round multi-stack mag could be developed.
And both the 6.5 and 6.8 work on the current lower receivers!