Definition: A round is a single piece of ammunition. It may be a metallic cartridge or a shotgun shell.
The term "sending rounds downrange" isn't really accurate, because at the instant when it's fired, a round ceases to be a round.
Chances are the term derived from the simple fact that almost all ammunition cartridges are cylindrical, and thus can be called round.
One may also refer to a 25-shot session of skeet shooting as a round.
- Russ Chastain
Also Known As: Cartridge, shell, ammo, and ammunition are all used to mean round. SOme folks even say "bullet," but that is incorrect - the bullet is just the projectile.
Examples: "How many rounds are in that gun?" "How many rounds did you fire?"