Abstract: An electromagnetic shear lock comprising an electromagnewt having an E-shaped cross section with a coil positioned about the middle leg of the E is mounted in a doorway and an armature having a central projection is mounted to the door, where the middle leg of the E is shortened to define a recess to receive the armature projection and provide mechanical reinforcement against shearing when the electromagnet is energized. The inner edges of the outer legs of the E and the edges of the armature projection are matingly beveled to prevent binding when the electromagnet is de-energized and an airgap is defined between the middle leg of the E and the armature projection to overcome any effects of residual magnetism.