90 grain has 166" less drop than a 77 grain .223 and about 60" less wind drift at 1000 yards....
It will be as popular as the Creedmoor.
No, because much of the Creedmoors fame is bolt actions. There’s no reason to use this in a bolt action when you have the .22-250 right there, or for that matter, the 22 Creedmoor. Also, ammo will not be cheap for a long time, which is the draw to an AR in 5.56/.223.