A lock cylinder having a keyway includes a first plurality of guide channels. A plurality of cup-shaped pins is movably disposed within the first plurality of guide channels. Each cup-shaped pin of the plurality of cup-shaped pins extends across the keyway. Each cup-shaped pin of the plurality of cup-shaped pins has an engagement protrusion. The first plurality of guide channels conform to the shape of the plurality of cup-shaped pins to allow movement of the plurality of cup-shaped pins in a first direction while restraining movement transverse to the first direction. A plurality of biasing springs is positioned to bias the plurality of cup-shaped pins in a direction toward the keyway. A plurality of racks is movably disposed in a second plurality of guide channels. Each rack of the plurality of racks has at least one engagement groove to selectively receive the engagement protrusion of a respective cup-shaped pin.