Alec Baldwin was sloppy and reckless with firearms on the set of “Rust” before the fatal shooting of cinematographer Halyna Hutchins, prosecutors have contended. According to court documents obtained by ETonline, the 66-year-old leading man engaged in “horseplay” during firearm training, including one instance when he fired a blank round at a crew member, whom he’d been using to establish his line of sight. Prosecutors further alleged Baldwin was also “erratic and aggressive” during filming, contributing to safety concerns on set. Baldwin would also allegedly use his prop firearm as a pointer, relying on it to acknowledge and direct different...