Methods facilitate inserting a cardiac lead into a patient's vasculature. A cardiac lead system includes a cardiac lead having a lumen, and a guide member displaceable within the lumen. The guide member includes a guide wire extension that extends distal to the elongated body of the guide member. The guide wire extension is dimensioned to pass through an external distal opening of the cardiac lead lumen. Engagement of stop features or a stop mechanism of the cardiac lead system provides a push point for advancing the cardiac lead system through the patient's anatomy.