There are a lot of variations of gun control being debated, but not in regard to an automatic weapons ban. They are already illegal in general, and it doesn't matter whether Murdoch is talking about the US, Britain, or Australia. Probably he was referring to semi-automatic weapons, which because they are already deeply ingrained (in the US at least) in law enforcement and the hunting culture (a large number of shotguns, hunting rifles, target weapons, in short the "acceptable" types of firearms are already semiautomatic), debating banning semi-automatic weapons is an exercise in futility as well as inanity.
It would probably be more useful to talk about banning cheap weapons of any kind, and/or large capacity capability for firearms.
I personally think the most effective discussion would be in regard to personal responsibility for access to weapons, access by children and by anyone for whose use they are not intended. Safety proof them, separate the guns from the ammo, and lock both securely. Those things and maybe some other relatively simple and doable precautions might lessen a certain category of gun related tragedies.