Lever-action Mechanism

Modifying your firearm with a new lever-action firing mechanism, you can now attack twice, instead of once, whenever you take the Attack action to use your firearm on your turn. The extra attack action must be used to take a shot with the firearm, and cannot be used for a spell, or any other action. 

Additionally, this feat requires proficiency in Firearms. 

This feat should not be taken on classes which already get the Extra Attack class feature.