Guidewires and related methods for percutaneous crossing of an occlusion in a blood vessel are disclosed. A guidewire can include a core member and a jacket member. The core member can extend from a proximal end portion to a distal end portion, with the distal end portion including a first segment, a more distal second segment and a more proximal third segment. The first segment can be configured to encourage prolapse by way of a short taper or a diameter-reduced portion. The jacket member can surround at least the distal end portion of the core member. A method can include advancing a distal end portion of the guidewire through the natural lumen of a blood vessel to a location near an occlusion. A longitudinal pushing force can be applied to a proximal end portion of the guidewire, thereby causing a first segment of the distal end portion to prolapse.
