Unless you have some 'common ammo' restriction, there are much better rounds for use in a bolt-gun that are around the same cost, or just a tad more, as the per-round cost of grendel.
Grendel was made to work within the restrictions of a standard AR-15 mag well, and it does yeoman's work given those restrictions (right barrel, right ammo load, 800Y and low MOA is quite doable). That said, you'd be better served in a different caliber for a bolt gun. (Again, unless you are sharing across platforms and have other considerations)