X2 passes to X1
X1 passes back to X2 who takes quick shot
X2 passes to X3
X3 passes back to X2 who takes quick shot
X1 moves to X2 spot
X2 moves to X3 spot
X3 gets in back of line
X4 moves to X1 spot
Repeat Drill

Variation: Instead of two shots can run through twice for four shots or three times for six shots.