Described herein is a method for recycling aluminum alloy wheels. The method includes the steps of providing a feed of aluminum alloy wheels of a particular alloy; fragmenting a quantity of the aluminum alloy wheels into a plurality of fragments; subjecting the plurality of fragments to shot blasting to remove surface impurities from the plurality of fragments to produce a plurality of shot blasted pieces; separating the plurality of shot blasted pieces into a plurality of larger shot blasted pieces and a plurality of smaller shot blasted pieces; and, estimating a composition of the plurality of larger shot blasted pieces by selecting multiple shot blasted pieces from the plurality of smaller shot blasted pieces and then measuring the composition of the multiple shot blasted pieces.