Three different Lead sling bullets, one with the remains of an inscription.  The slingshots are all oval shaped and symmetric with a thick patina coating.  These were used to fire towards Rome's enemies and became heavily used during the later roman period with staff slingers. 

The third sling shot (and closely the 2nd) has some significant weight and size.  The likely conclusion is that the first one was used by a hand sling shot thrower, while the later ones were used by the more powerful staff slingers. 

These projectiles could be deadly when fired at range and would add to the turmoil of archers and the hail of plumbata that the Roman army could put on the enemy.

The 2nd and 3rd slingshots appear to have large "dings" in them that appear ancient due to the patina still covering them.  The slingshots were likely used in battle as a result of these damage marks. 

Possible inscription:

What remains of an inscription is visible on one side of the frist slingshot.  It is unclear what the inscription says, however it appears to be a number ...XIV... perhaps indicating the name of a Legion or Cohort in which it was used. (1)

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