The provisions of this act do not apply to actions for deceit, breach of contract, or expressed or implied warranties, or for injuries resulting from failure of firearms to operate in a normal or usual manner due to defects or negligence in design or manufacture. The provisions of this act do not apply to actions arising from the unlawful sale or transfer of firearms, or to instances in which the transferor knew, or should have known, that the recipient would engage in the unlawful sale or transfer of the firearm, or would use, or purposely allow the use of, the firearm in an unlawful, negligent, or improper fashion. For purposes of this section, the potential of a firearm to cause serious injury, damage, or death as a result of normal function does not constitute a defective condition of the product. A firearm may not be deemed defective on the basis of its potential to cause serious injury, damage, or death when discharged.