also: pistol formation · pistol backfield
The quarterback about four yards deep with a back directly behind him. A compromise between under center and shotgun that keeps downhill running available.
The quarterback aligns a few yards behind the center, shorter than a full shotgun drop, and the running back lines up directly behind the quarterback rather than beside him.
What it is for is keeping two things that normally trade against each other. A shotgun quarterback sees the defense better and gets the ball cleanly, but the back beside him has to run laterally before he runs downhill, and his alignment tells the defense which side. A back directly behind the quarterback can run downhill to either side and gives nothing away, and the quarterback still gets a direct snap.
The corpus carries a good worked example of why a program adopts it: a youth coach merged a Wing-T with the Pistol after a 9-year-old quarterback could not handle under-center mechanics and kept muffing snaps. Moving him back four yards and direct-snapping fixed it, and the base plays developed faster.
pistol formationace, shotgun**Pistol is a backfield chip value in Playside's diagram editor.** Coaches select it from a dropdown today with nowhere to read about it.
The reason it appears in youth football is usually mechanical rather than schematic. Under-center exchange is a genuinely difficult skill for young players, and a direct snap removes it without giving up downhill running the way a full shotgun does.