Before any prop or replica firearms and/or weapons can be used during filming, the production companies must first talk to their film contact and the police. A film weapon CAD number will then be issued and this will let officers know that the weapons and firearms being used are for filming purposes.
If a live weapon is going to be used, someone with the proper license to hold that firearm or a registered firearms dealer must be on the set. Even if the weapon is only firing blanks, a license holder or registered firearms dealer should still be present.