Two well known bolt action rifle manufacturers have expressed interest in offering regular production 6.5 Grendel bolt action rifles.
The availability of low cost surplus ammo of the 5.56 and 7.62 has to do with NATO adoption and manufacture on a global scale. Adoption of a new cartridge by NATO is not a short process and is very political. Reaching the level of bargin prices would take years to realize as it did for both the 5.56 NATO and 7.62 NATO.