Re: I'd support an Aussie-like system
Just an FYI for those that are not aware of how Australia works.
The basic requirements are that you are licensed first (need to complete a mandatory safety course and have a genuine reason - and self defence is not a reason), and then once licensed (takes 4-8 weeks from application), then apply for a permit to acquire (takes 1-2 weeks), and then once you have the permit, you can go out to purchase and own a long gun (typically bolt action or lever action, semi-auto rifles are heavily restricted to mainly primary-producers and professional pest controllers). Your license defines what you can own, not whether you are actually allowed to purchase it (that's the role of the permit to acquire, which you need 1 permit for each firearm, it's a mechanism to stop you from buying 50 rifles from 50 different places). Also all firearm trades must go through a registered dealer or broker (who report to the state's licensing body).
The process for a rifle/shotgun generally takes 3 months, from doing the initial safety course to being able to actually own a firearm. Firearms must be stored in a safe, with the action broken and ammunition stored separately when not in use.
The process for a handgun takes 9-12 months, as you need to be a member of a pistol/rifle sporting club, complete their courses and get a few forms filled out. Additionally in order to get a Cat H license (concealable firearms license) you need to be a member of a club for at least 6 months before you can apply for the license. Permits for handguns typically take longer as well, as the club also will approve the type of handgun as well. Having a Cat H license, also means you have to attend a number of qualified shooting events at a club as well each year. (typically 6+ shoots per year). Handguns also have barrel length and magazine capacity restrictions as well.
Police under the various State's Weapons Acts are allowed to do unannounced spot checks to ensure compliance, so they can come around at any time, inspect your storage and what firearms you have. Some states do have limits on the number of firearms you can own, but typically the responsible owners typically self limit to 2-3 rifles and for those that have a handgun license to 2-3 as well. Typically if on an inspection if found to have a larger number of rounds (10K+ total), you may get a formal "please explain" investigation as well, as it's recommended to only keep on hand what you need as well.
Generally for those in the sporting aspect, generally stick to the smaller calibres (ammo here is expensive), so you will never see any .50cal rifles, you typically wouldn't get approved to own one nor are there any ranges that can take the calibre. For example, the pistol club my son and I attend is limited to 22LR for rifles, or any non-magnum pistol calibres as the ranges themselves cannot safely handle anything bigger. If we wanted to run say .338 Lauper for 1000m shoots, then the closest range that can use that is a 2hr drive away, so that's a no go for us. As for shooting on public land (an online permit in most states) or for a farmer, both parties ultimately will have a say in what can be used where. (Bunny or fox hunting in result in being restricted to .223 at most, but typically 22LR or 22WMR).
Short note: "action broken" typically means the bolt has been removed or for a shogun, it's stored in the open position. Most states recommend a tigger lock to be applied as well. Detachable magazines must also not be stored in the firearm as well.
I'm happy with most aspects of Australia's firearm laws, as it tends to keep the dickheads out of the sport (due to the time factors involved), the only part that most people dislike is the ban on suppressors. But the fun fact, Australia has more firearm license holders and firearms out there now, than we had when the Port Arthur Massacre occurred. (This event is what lead to mass changes in Australian law, typically removal of semi-auto rifles and hand gun restrictions). Also our armed assault events (as reported by the police) typically involve bladed weapons and not firearms, so the numbers reflect that as well.
And to note, if you are not a law abiding citizen, then none of the above applies and you can generally get whatever is available on the black market.
Now, could the US adopt Australian style laws? I don't see that happening anytime soon, due to the number of firearms out there and would ultimately require a change to the 2nd Amendment, in defining what 'arms' actually entails. Remember, when the 2A was written, the invention of self-loading firearms was still a while off.