Here are some rules regarding the use of firearms on a film set.
Whose responsibility is it?
Safety on set is the responsibility of the producer, the director and the first assistant director (First AD). The First AD is the producer’s voice on set: responsible for on set safety calls with input from the safety supervisor and armourer. He or she will have been briefed by the producer, who provides a risk assessment and an industry standard safety report.
The armourer is responsible for inducting anyone handling the firearm on set and safely keeping the weapons. Police and neighbors should be notified by the production office of the presence of firearms and intended blank firing to avoid distress and false alarm calls.
Each day, the First AD and the armourer should discuss the proposed schedule of use and the safe storage of the firearms between use. The First AD should be satisfied that the guns brought to set are safe and unloaded and that no live ammunition is on set.
The First AD must, if it hasn’t been possible in rehearsal, arrange for all cast who are scheduled to be handling the firearms on the day to be inducted in the safe handling of the firearm that they will be using.
The armourer (who holds the guns) will then be on standby to issue firearms as required by the script. This is where it all gets a little Full Metal Jacket.
Each time a gun is handed to a performer, the armourer must open the weapon’s breach and present it to the performer with verbal confirmation such as, “The weapon is clear”.
When the performer is satisfied that the gun is not loaded they should audibly confirm “Clear”.
When it is returned to the armourer following the take, the same clear verbal confirmation is required.
https://theconversation.com/explainer-the-rules-for-shooting-on-film-sets-71797