Abstract: An axial split-pin tumbler lock having a rotatable operating element and a fixed element configured to define a shear plane therebetween, and wherein aligned bores extend in the two elements on opposite sides of the shear plane, with specially configured code pins and drive pins slidable in the bores in the elements across the shear plane, the specially configured code and drive pins being so constructed that they will bind or hang up in the respective bores in any number of axial positions during an attempt to pick the lock, thereby giving multiple and differing false readings of an unlocked condition of the lock and rendering it pick resistant.