A scope mounting system having one or more components formed of a zinc alloy, preferably an alloy of zinc, aluminum, magnesium and copper. In one form, the component is formed of an alloy of zinc with about 3.5 to 4.3 weight percent aluminum, about 0.02 to 0.05 weight percent magnesium, and about 2.5 to 3.0 weight percent copper. The scope mounting system preferably includes one or more components, such as a base and/or rings, at least one of the components being formed by casting.