You cant have ANY semi-auto weapon larger than a handgun here, not even a .22
You can only own and keep a handgun if you are a registered member of a pistol club, you keep the weapon at that club under lock and key, and you have a pistol licence .(unless you own land If you are a property owner with more than 200 acres, or have the permission of such a person to shoot on their property, weapons and permits are pretty easy to get, both rifles and handguns, unless of course you have a criminal or psychiatric history)
True assault weapons (pistol grip, 30 rnd box mag, flash suppresser) were allways fairly rare, but were available fairly easily on the 'not-so-legal' market, I doubt that has changed much, if at all.
Bolt action sporting rifles are fine, no problems keeping one of them at all, requires a shooters permit, but you can get one of those from any Police station.
Shotguns are fine, so long as they arent semi-auto or pump action.
The REAL stupid part, lever action rifles are a big NO NO !....who the hell ever commited a crime with a lever action .30/30 in the last hundred years???
It's nothing new about the buy back scheme being a total crock, everyone I know who handed in anything was vastly overcompensated, including myself.
I handed in 3 pieces of rusty crap, and was given enough to buy a brand spanking new Carl Gustav .270 with a Ziess 3~9X variable.
Everyone I know who had any semi autos of actual value, didnt hand them in.
Whole thing was and still is a sad joke, blatant over-reaction by the people who have no need of, nor use for any weapons, giving those of us who at times do a few more hassles in getting /using one.
BTW firearms crime hasnt slowed one little bit down here, infact Sydney and Melbourne 'crime families' seem to be shooting each other at an alarming rate just lately.
Really all it means is that there are a hell of a lot more illegal weapons in Oz than there used to be....the weapons were allways here, it's just now they are banned.
Doesnt mean people dont possess them though.
If guns are outlawed, only outlaws will have guns. As the say.
Apart from handing in some busted old crap semi-autos which were useless anyway, the gun laws havent really effected me much, except I had to update my licence, and buy some PVC tubing.
In fact I spent last weekend destroying some evil cans with a mate's Desert Eagle....havent chased many porkers though, I dont like the idea of fumbling with a bolt when 100kg of pissed off bacon is charging me

I used to relish the thought with an SLR in my hands.
Just as an afterthought, as far as I am aware, it is legal to own and keep a fully automatic assault rifle or submachinegun, or a full size machinegun for that matter, if you own a boat of ocean-going capability. Something to do with international law regarding defence against pirates !!