Take a close look at the first picture. In it you can plainly see stuck only into the skin of the gator's skull a .38 Spl. +P.
The next picture is that same slug pried off the skull.
Now go back and look at the first picture. If you look hard you can see a couple of other holes in the gator just behind the skull.
Just behind the skull is where the bangstick should have hit the first time......because a +P .38 Spl will not crack the skull of a almost 11 foot gator.
And from experence I can tell you that a .357 Mag. will usually not do it either. Our goal is always to place the bangstick strike in such a way that it will hit the base of the spine/skull joint. This will kill them quickly and humainly. Sadly it is not always done the way we'd like the first time.
My point is that the skulls of gators......and I would expect of crocodiles to a ever greater extent as they get larger......are very tough to penetrate. A glancing blow will do nothing unless delivered by a serious round. And it's a far better bet if that round is firing a solid of some sort.....not soft lead.
This is not to say a 12 ga with a slug would not under almost all situations prove very useful......just that maybe a rifle round with a jacketed solid would be better?