Sling (weapon)
Impact

Ancient poets wrote that sling-bullets could penetrate armour, and that lead projectiles, heated by their passage through the air, would melt in flight. In the first instance, it seems likely that the authors were indicating that slings could cause injury through armour by a percussive effect (i.e., the energy of a sling-bullet delivered at high velocity causing blunt trauma injury upon impact) rather than by penetration. In the latter case we may imagine that they were impressed by the degree of deformation suffered by lead sling-bullet after hitting a hard target.

According to description of Procopius, the sling had an effective range further than a Hun bow and arrow. In his book Wars of Justinian, he recorded the felling of a Hun warrior by a slinger:

Now one of the Huns who was fighting before the others was making more trouble for the Romans than all the rest. And some rustic made a good shot and hit him on the right knee with a sling, and he immediately fell headlong from his horse to the ground, which thing heartened the Romans still more.
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