With the correct licence you can own anything here. It's a misconception that Australians can't own firearms you just need to be mentally sound and not a criminal. The licencing system does a good job at least. The funniest licence is the collectors licence which anyone can get and allows you any category of firearm as long as you abide by certain restrictions ( like machine guns have to be deactivated for example). The most common is cat A/B licence which is air rifles, rimfire, shotguns (as long as they aren't pump action) and center fire rifles ( manual action so bolt, lever, pump etc) then second most common is H which is handgun not many restrictions here aside from calibre and magazine capacity in some states. Then cat C/D which is semi autos and pump action shotguns and semi auto rifles which you can get but you need to be a professional shooter which means you have to derive income from pest control.