Hannah Gutierrez Reed, the armorer and key props assistant on the movie set, said in the complaint that she bought live ammunition she believed to be dummy rounds.
The actor said his production company decided to make the switch to rubber guns after the shooting death of cinematographer Halyna Hutchins on the Rust movie set last month.
The American Film Institute created a scholarship in honor of Halyna Hutchins, who was killed by a prop gun on the set of "Rust." The fund will support aspiring female cinematographers.
It isn't the first gun death on a set, but Hutchins' shooting has refocused attention on the safe use of firearms by the entertainment world and raised the question of whether they should be banned.
The actor fired the prop gun that killed a cinematographer during filming of the movie Rust, police said. On Friday, Baldwin expressed "shock and sadness" over the incident.
The death of director of photography Halyna Hutchins on a film set in Santa Fe, N.M., is a reminder that prop weapons can pose a serious risk. But Hollywood history includes only a few such incidents.