According to Roland's plan, the firing would not stop once it had started.
The first, five rounds of the volley turned around 20 beasts in the first row into ashes. Then, in the free shooting time, the rapid firing, emptying ammunition, paired with the ignition of black powder, created a grand roaring momentum.
Thus, as the firing continued to ring out, the atmosphere created by this scene ushered in a new upsurge. The frequent blasts created a cloud of almost endless dust that made the surrounding 1,500-foot radius look like an impending doomsday. Occasionally a ricocheting stone would crush a cage and if the beast survived it would flee, choosing to run away, instead of rushing to the wall.
Fear had overridden their bloodthirsty instincts.
However, only a few would escape this land of the dead.