This has been weighing on my mind recently, specifically after the Orlando shooting and after hearing several people calling for the implementation of British and Australian style gun control within the United States.
Since the buyback after the 1996 massacre, Australia hasn’t experienced a mass shooting and even experienced a considerable reduction in firearm homicide, according to the law’s proponents. However, the success of Australia’s gun control program isn’t as easy as such to conclude. Empirical evidence shows that the rate of mass shooting incidents in Australia and its neighbor New Zealand, a socioeconomically similar country, did not differ significantly before or after the buyback program, despite New Zealand retaining civilian ownership of firearms banned in Australia in 1996. This here casts some doubts on the lack of mass shootings in Australia, post-1996.
Moreover, Australia’s firearm homicide rate was falling well before 1996, and the continuation of this trend following the buyback program doesn’t prove that it works. A paper recently published in the International Journal of Criminal Justice noted that not a single study on this matter has found a statistically significant impact of the Australian legislative changes on the pre-existing downward trend in firearm homicide.
Further study by the University of Melbourne show that “The results of these tests suggest that the NFA (National Firearms Agreement) did not have any large effects on reducing firearm homicide or suicide rates.” 
Additionally, a study published in the British Journal of Criminology found that there was no evidence that the NFA had any impact on reducing firearm homicide. They did find that it may have helped reduce firearm suicide, but they that societal factors were already reducing suicide rates.
And finally, a 2009 study the Australian Institute for Suicide research studied how the NFA effected suicide rates and found the following: “The implemented restrictions may not be responsible for the observed reductions in firearms suicide. Data suggest that a change in social and cultural attitudes could have contributed to the shift in method preference”.
So no, Australia is not proof that gun control works.
The UK, on the other hand, is a similar story. Not to mention that other countries define crime differently than in the US, so its not always an equable comparison when looking at crime statistics. For instance, in 2011, the UK’s Home Office noted that there were only 636 murders provisionally recorded for 2011. Chief Inspector Colin Greenwood shows that someone has been murdered once the murderer has been at least convicted. Per the report: “Since 1967, homicide figures for England and Wales have been adjusted to exclude any cases which do not result in conviction.” As a result, murders that have not been solved are not included.
Thus, we cannot get an accurate picture of crime in the US and the UK, at least for murders. Nonetheless, the UK gun ban was instituted in 1997, and between 1997 and 2011, the average number of firearm offenses period was 31% higher than in the previous 1990 to 1996 period.
In England and Wales, homicide-by-stabbing rates are 5 times higher than gun-related homicide rates, showing that people with the intent to kill will do so, no matter the method. This is why TOTAL homicide counts are extremely relevant. And when we look at When these total homicide rates, we see they, as the firearm homicides, did not improve after the 1997 ban.
Per the UN, the UK has one of the highest per capita crime rates in the world. (specifically 4th highest out of 81 countries observed based on 2002 data). Several years later in 2008, the UK held a violent crime rate of 2,034 per 100,000 population compared to the 446 rate in the United States.
In the United States, there were 403 incidents of “violent crime” per 100,000 people in 2010, which dropped to 371 incidents in 2013. Contrary to the United States, there were 1,797 Incidents of violent crime per 100,000 people in 2010 for the United Kingdom.
However, “violent crime” is defined more broadly in the United Kingdom, meaning official figures can be adjusted downward to align it with how “violent crime” is defined in the United States. After doing that, their rate is still near twice that of the U.S. at approximately 776 incidents a year.
The whole thing about not “needing” assault-grade semi-auto and automatic rifles for defense is disingenuous. Not to mention that it’s called the “Bill of Rights”, not the “Bill of Needs” The Second Amendment does not discriminate between pistols, shotguns, semi-automatics, etc. Not to mention the whole “shall not be infringed” section of the Amendment, with “infringe[d]” meaning “to violate; to break laws or contracts; to destroy; to hinder.”
William Rawle, in one of the earliest commentaries on the Constitution (A View of the Constitution of the United States) says that “No clause in the Constitution could by any rule of construction be conceived to give to Congress a power to disarm the people. Such a flagitious attempt could only be made under some general pretense by a state legislature. But if in any blind pursuit of inordinate power, either should attempt it, this amendment may be appealed to as a restraint on both.”
To add to that same “logic”, you can have the right to free speech on the First Amendment, but you don’t need the internet. The right to freedom of the press? You don’t need radio. The freedom of religion? You don’t need Mormonism.
“Shall not be infringed” means just that, be it from today’s English, or the original 18th century language.
And as I have said previously, the United States is more safer since the 1990s, as the gun homicide rate is down 50% since 1993. And so is crime in general. Not to mention that mass murders (where it is defined as 4+ murders) account for 0.2% of all murders, and 0.001% of all deaths. Furthermore, data from the Global Study on Homicide that ranks all 219 countries by homicide rate shows the United States ranks 111th, with 4.7 murders per 100,000 population, well below the average rate of 8.6 and right at the median of 4.7.
Furthermore, a ban on “assault rifles” (whatever those are) will not prove effective here in the United States. And there’s historical data to back this up. Between 1983 and 2012, a period of three decades, the Congressional Research Service shows that 547 people were killed in mass shootings, or only 18.9 per year, accounting for less than 1% of all firearm homicides.
Assuming that firearm bans were 100% effective (and the evidence shows they are not) banning rifles and shotguns in the United States would have at best very small effects on gun violence. Rifles have only confirmed to have been used to murder 322 people in 2012. That’s only 3.6% of all firearm homicides and only 2.5% of all homicides in general. And shotguns were only confirmed to have been used to murder 303 people in 2012, which is 3.4% of all firearm homicides and 2.3% of all homicides in general.
It’s also worth noting that this 322 number for rifles from 2012 is even smaller when you take into account justifiable killings by police and private citizens, which reduces it to 266 homicides in 2012.
For comparison, that same year, there were 1,589 homicides committed with knives, 518 committed with blunt objects, and 668 committed with hands or feet. Thus, you’re more likely to be strangled, clubbed, or stabbed to death in the United States than be shot and killed by an “assault weapon”. Should we ban hammers, clubs, and knives as well.
And what about large capacity magazines? According to a Department of Justice report, “Specific data suggest[s] that relatively few attacks involve more than 10 shots fired”. The report also notes, “the few available studies on shots fired show that assailants fire less than four shots on average, a number well within the 10-round magazine limit”.
Thus, banning magazines over 10 bullets isn’t likely to effect crime much at all, even if criminals adhered to the law. The DOJ study reports that “despite a doubling of handgun LCM [large capacity magazine] prices between 1993 and 1995 and a 40% increase in rifle LCM prices from 1993 to 1994, criminal use of LCMs was rising or steady through at least the latter 1990s, based on police recovery data from four jurisdictions studied in this chapter. Post-2000 data, though more limited and inconsistent, suggest that LCM use may be dropping from peak levels of the late 1990s but provide no definitive evidence of a drop below pre-ban levels. These trends have been driven primarily by LCM handguns, which are used in crime roughly three times as often as LCM rifles. Nonetheless, there has been no consistent reduction in the use of LCM rifles either [and] the consistent failure to find clear evidence of a pre-post drop in LCM use across these geographically diverse locations strengthens the inference that the findings are indicative of a national pattern.” 
So a ban on “assault weapons” and high cap mags not do anything to deter murder.
Someone asked me about military and law enforcement surplus being a way for people to get a hold of these guns, to which I replied that not everything with such a surplus is for sake on the civilian market.
For civilian use, military surpluses are limited to the more minor things, equipment, tents, radios, and yes, even guns. A glance at the website for “Major Surplus and Survival”, for example, shows the following categories: “Ammo Cans & Containers, Apparel & Footwear, Backpacks & Bags, Gas Masks, Outdoor & Camping, Tools & Equipment, Vehicles & Transportations, Weapon Cases”. And no, Vehicles & Transportations do not include things like tanks and whatnot.
However, a good chunk of military surplus items have been transferred to law enforcement agencies thanks to the Department of Defense’s 1033 Program established in 1997, and has had a transfer of $5.1 billion in military hardware between 1997 and 2014. Statistics on this program doing back to 2006 show that much of it was small purchases, no more than a a few thousand per month, save for late 2006 and the first half of 2012. Current averages up until 2014 are between 3,000 and 4,000 purchases per month. Stats further show that the top categories are Mine resistant vehicles, Trucks (utility), Aircraft (rotary wing), Helicopters (utility), Truck tractors, Trucks (cargo), Image intensifiers (night vision), Airplanes (cargo-transport), and Helicopters (observation), and further shows that “about 1/3 of the money spent on the 1033 program went to MRAPs, trucks, rotary wing aircraft, and helicopters”
Now I agree that militarizing the police is a bad idea, as the following source makes the case for that and I think that the 1033 Program should at the very least be reformed. As far as law enforcement surplus, I have found no statistics on that, so I cannot accurately comment on such.
I’m all for background checks (which can be done in minutes nowadays) and prohibiting those with mental illnesses or a criminal record from obtaining firearms. The major problem with that, however, is that mental health records are kept at the State level, and not transferred to a Federal system.