Okay, let's start by debunking this nonsense. For the first couple of years after the ban, which was a partial ban, was passed, crime rates did increase. However, after that and moving forward, crime rates have decreased significantly, and murders by guns are about half what they used to be.
FactCheck.org : Gun Control in Australia
Sometimes, you should do your research before using bad propaganda to make your case. Now, if we want to compare Australia to the US, then we actually can discuss why a gun ban there might be more or less effective than in the US. For starters, based on the number of guns turned in, which was just over 640,000, and based on their population of 22 million, that equates to on gun for every 34 people. Now, let's look at similar statistics in the US. It is estimated that there are around 300 million guns in the US, and we have a population just over that number, so we have one gun for every person, not one gun for every 34 people. Try confiscating 300 million guns versus confiscating 640,000.
You see, it's important to make arguments that are not only true, but also make some sense.