The use of B.B. guns, slingshots, bean-shooters or any like appliance or apparatus is hereby forbidden in the city and none of them shall be discharged within the city, either on public streets or places, or on private property; provided that it shall not be unlawful to use or discharge said appliance or apparatus mentioned in this section on any range or field designated for the use and discharge of such appliance or apparatus by public authorities. (Prior code § 6.04.010.)