the whole nine yards

Etymology:

• During WWII, U.S. Airplanes were armed with belts of bullets which they would shoot during dogfights and on strafing runs. These belts were folded into the wing compartments that fed their machine guns. These belts measure 27 feet and contained hundreds of rounds of bullets. Often times, the pilots would return from their missions having expended all of their bullets on various targets. They would say, I gave them the whole nine yards, meaning they used up all of their ammunition.