I shot a mule deer buck in the right side back ribs while he was quartering away from me at 80 yards. My intent was for the shot to angle forward into the lungs. The bullet was a 120 grain Ballistic Tip from a 260 Remington Tikka T3. Muzzle velocity is 2900 fps. The bullet hit in the area of the last four ribs and exploded on contact. Luckily, fragments of ribs pulverized the liver. The deer jumped around in a circle, but basically didn't go anywhere. Then he dropped. Lucky for me because my two follow ups at the moving deer missed. The bullet failure was total. I never found any of the bullet except for little bits of jacket and lead. The only damage to the deer was to the back ribs on the right side and the liver. The deer bled out.
The 6.5mm 120 BT is a wonderful bullet for target shooting out of my gun, and might work fine on deer at a distance, but not at close range. I am tending towards the 130 Accubond now although that BT load would probably be fine on pronghorn.