How could or should the 6.5 mm Grendel be improved?

[stanc]

Would the improvements in performance over the Grendel really be worth the additional weight?

Increasing mag well size would add negligible weight, but enable use of thicker-walled, polymer or carbon steel mags. As far as the benefits of beefed up bolts, etc, I dunno.

I think our best bet here is to get a LMG built to accommodate the Grendel and see what kind of attention that attracts.

Concur. Sadly, I doubt that anybody here has the $$$$$ to finance such a project.

Then if we can get a steel core FMJ bullet developed, so we can prove our assumptions.

The mythical Wolf steel case ammo reportedly has a steel core FMJ. If it ever reaches these shores, that should provide a good basis.

However, some aspects of the military utility of 6.5 Grendel could be tested using currently available COTS rifles and ammo. It just requires sufficient interest on the part of Grendel proponents.