To take a chance and reach for some goal or desire.

While kids rode on a Merry Go Round, those on the outside had a chance to reach for a gold (or brass) ring hanging outside the carrousel. If he or she managed to grab it, (s)he recieved some prize - often a free ride.
Stan grabbed for the gold ring, but fell flat on his face. "grab for the gold ring"
by LWM June 3, 2006
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