snip
"There were 300, I think, to begin with, and then you hit 116. Why didn't you go back?" a reporter asked Operation Inherent Resolve spokesman Col. Steve Warren.
"Frankly, the aircraft expended 24 500-pound bombs, and all of their ammunition," Warren answered. "So they — they shot everything they had and then they had to go home."
snip
U.S. officials settled on a plan to drop leaflets on the trucks about 45 minutes before the raid, warning the drivers that an attack was coming, while U.S. pilots flew low passes over the area. Planning all that took time.
Much more at link if you dare.
http://www.washingtonexaminer.com/u.s.-ran-out-of-ammo-in-attack-on-isis-trucks/article/2576958