Instrument 004 · ballistics
Fire a group of shots with the same heading and a small gap between their starting positions. Watch how that starting segment changes as the shots cross the box. With dispersion on, the segment stretches into a filament and folds across this finite run. Turn dispersion off and the group holds. A focusing geometry can produce a caustic on a dome. This dispersing model shows how the group stretches and folds during a finite run.