Re: rec's for a truck gun w/ hog in mind
AK is pretty cheap still (about the same as a handgun) and they work forever and reliable. The round is plenty to take down hog (not the perfect round but certainly adequate) and the gun is compact, especially if you put a folder stock on it!
No fancy schmancy optics or gadgets needed, just point and blast away, and you have 30 rounds to try and connect! I would say whatever you choose, pick a rifle; a shotgun is just too limited in range if you get a longer shot chance.
"Loud noises don't end gunfights.... well placed shots do."