The most common site of wandering bullet is:-

Bullet emboli/Wandering bullet : Vascular embolization is associated with small caliber, low velocity bullet, and involves the aerial system. It should be suspected whenever there is a penetrating bullet wound with failure to discover the bullet in the expected region or to visualize the bullet on routine X-ray. The most common sites of entry for a bullet are the aoa, right atrium and ventricle, pulmonaryaery, and the inferior vena cava in order.