Not many. And ranchers and station owners have licenses other people cannot get.
You have to prove why you need any gun in Australia and you can only get certain types of guns with certain licenses. No state decided good reason, no license, no gun. And they did require people to turn in their weapons. I have read the articles where people said they had to turn them in.
Like nineteen pages of forms to fill out is why most people just give up. Meanwhile a cop was gunned down by a sniper shortly after that law was passed and the PM earlier stated that “we’ll be safer now” - how many gun deaths have happened since? Yep, sure did work, didn’t it?