A lock includes a core rotatably disposed within a barrel. A plurality of tumbler pins are disposed in shafts in the core and communicate with a keyway. A side-pin shaft intersects each tumbler pin shaft at a selected angle. Each tumbler pin includes a side hole at a position along its length that aligns with the side-pin shaft when a proper key is inserted. An independent side pin is disposed in each side-pin shaft. One end of each side pin rests against its associated tumbler pin and the other end of each side pin is tapered and extends into a channel in the barrel. The side pins are biased outwardly by a spring towards the channel. The angle at which each side-pin shaft intersects each tumbler shaft may be different. The spacing between tumbler pin shafts may be different.