US Patent 9810506 Self-captured detent mechinism

A revolver has a detent mechanism providing positive mechanical engagement between the cylinder yoke and the frame. A housing mounted on the frame has a spring biased plunger that transversely engages a pin. The pin projects from the housing and engages a recess on the yoke when the revolver cylinder is closed. The pin is biased into engagement with the recess by the plunger to maintain the revolver closed and the chambers of the cylinder in precise alignment with the barrel during firing. Manual force applied to the cylinder can overcome the biasing force and permit the revolver to be opened and closed.