Gunshot wound to the abdomen by George Mimmis

There are major organs, massive blood vessels and bowels full of bacteria inside the abdomen plus the spine on the oppositeside. Hit the aorta,

 death in 2 minutes, vena cava 4 minutes. Hit the large vessels leading to an organ, less than 10 minutes in most cases. Hit a major organ, depends on which organ and where it could be quite fast. If the bullet angles up, it could hit a lung or the heart. A direct heart hit is fatal, a punctured lung may be quick but medical care can reinflate the lung.