If you shoot a hog high there is good chance it will make it. A mid level chest shot that would put a deer down will let a hog get away most of the time. You have to shoot low, low and forward. The heart is at the bottom of the chest, like in the brisket on a deer. There have been tons of hogs live after being shot in only one lung. we take around 200 hogs a year between reg hunting and using the dogs and have seen so many survive on only 1 lung it isnt even funny. shoot low and they wont go far.