I am in a similar quandary with my next AR build. I have a few .223/5.56 calibres now, 7.62x39, and 6.8 SPC.
I am leaning towards 6.5 Grendel. Its got more punch than the .224 Valkyrie due to bullet mass. The Valkyrie will stay flatter and reach out supersonic a few more hundred yards, but with less overall energy. Since I have other rifles for reaching out past 1000 yards, I think the Grendel will come first.
I think the 6.5 ammo is also a little cheaper.
Thanks.
What I have heard is that the Valkyrie is not stable with the larger bullets.
I am in the same boat as you.... Where to next??
I built a long distance operator in 6.5 Grendel.
Ammo is tough to find. Everyone, even WalMart, has boxes of 6.5 Creed. Even The Bass Pro in Springfield didn’t have the Grendel in stock. Academy has an empty spot on the shelf. None of the local gun shops have it.
And it is a shame because the Grendel is a joy to shoot.