He or she is one of 822 registered firearm owners who collectively possess a total of 4,042 guns in postcode 2400; on average five per owner, one gun for every three people and an increase of 243 guns registered since 2017.

The stats are included in a website put together by Greens member of the Legislative Council David Shoebridge. He argues NSW law contains a "loophole" which improperly permits owners to claim multiple guns for the same reason.

The information was gathered through a Freedom of Information request to NSW police in 2017 and updated for data to March 2019. Mr Shoebridge excluded firearm collectors from the ownership stats.

NSW's biggest arsenal is in Moonbi, west of Tamworth, where a single firearm owner is licensed to own 311 guns. In 2017 there was an arsenal of 312 guns in the same postcode, 2353 - possibly the same person.

By comparison, there are just 467 guns in the Sydney postcode of 2030. The postcode, which covers the wealthy inner-city suburb of Vaucluse, has just 113 registered firearm owners, with the most well-armed owning 35 guns.

To get a firearm permit in NSW you need to have a "good reason ... directly related to the reason for the issue of my firearms licence". But there's no obligation to justify owning multiple firearms for the same purpose, typically for farming purposes or target shooting.

"Gun owners can endlessly recycle the same "good reason" to get their first gun and then their second gun, their tenth gun and their 300th gun," Mr Shoebridge said in a recent media release.

"It is impossible to see how any one citizen can establish a "genuine" or "good reason" to have dozens, or even hundreds of guns."

Robert Borsak, MLC for the Shooters, Fishers and Farmers Party said he didn't think there were too many guns in NSW.

"I don't, because I think if you look at the per capita number of firearms that are owned by law abiding citizens, it's not much more than it was 20 years ago.

"And of course the mix of those firearms is different too. There are no self-loaders, there are no semi-autos, there are no pump-actions (shotguns). Certainly none that are legal anyway."

Mr Borsak said the the licence holder in Moonbi has a right to own as many guns as he does.

"First of all, why should you or I even know that someone in Moonbi owns 300 guns? That information doesn't need to be public.

"He may have 300 firearms because he's a collector."

Mr Shoebridge's website numbers exclude collector's licences. Mr Borsak argued the numbers cannot exclude all collectors because a collector's licence does not allow a person to actually fire the weapons they possess and that therefore they tend to obtain regular class A or B licences.

"The two things that primarily make our firearms laws work are safe storage and universal background checking," he said.

"They're the two things that really keep us safe in the sense that people who shouldn't get their hands on firearms (don't)."

Mr Borsak said the website is 'mischief making' and blames it for an increase in firearm theft and said it serves no public benefit.

Last week police launched Operation Armour, which aims to target illegal black market firearm possession and gun theft across NSW. At the launch in Tamworth, police said stolen guns are routinely used in other crimes or as currency in the drug trade.

"What greater example do we need then here in Tamworth with the death of our officer, David Rixon, from an unlicensed firearm in the hands of a criminal," Assistant Commissioner Geoff McKechnie said, yesterday.

Senior Constable Helen McMurtry was hit in the throat by a high-powered bullet in Glen Innes in January. Eric Newman, an avid big game hunter, was one of Glen Innes' licensed gun owners and owned several. He fired two bullets - one hit officer McMurtry and Sergeant Mark Johnson, and he killed himself with the second.

In an interview in February the injured police officer questioned why there needed to be high calibre firearms in built-up areas.

"Have the firearms if you want them - that's your choice, freedom, that's why we are in Australia," she said.

"I do not know why they need to be in homes in (town) like that, on the main highway."