Dummy Round
An inert cartridge used for safe dry-fire and malfunction practice.
Also: dummy cartridge, snap cap, drill round
A dummy round (or snap cap, or drill round) is a cartridge with no powder and no live primer — typically with a brightly-colored case or polymer body so it cannot be confused with a live round. Dummies let a shooter practice loading, malfunction clearance, and dry-fire trigger work safely. Mixing a dummy into a live magazine (with a partner loading) is a classic flinch-diagnosis drill.