A man caught cooking meth in Northland was also a corner store for other drugs and guarded his business with powerful firearms including a .50 calibre machine gun.

William McKinley, 52, travelled to Northland from the South Island in 2020 to make meth at a secluded location. But he was caught as part of a police drug operation Hare, which targeted him as the kingpin of a nationwide distribution chain.

McKinley was jailed for 10 years yesterday when he appeared for sentence by Judge Gene Tomlinson in Whangarei District Court.

Tomlinson said: "Why anyone in NZ has a 50 calibre machine gun is beyond me. Why a drug dealer has it that's obvious but about as serious as it gets."

Tomlinson said it seemed McKinley's Northland undertaking was intended to be "one last cook, one last big opportunity for the big score" before his plan to settle down selling firewood in Queenstown.

McKinley got sentence discounts for his guilty pleas (15 per cent) and a cultural report outlining his difficult childhood and background as a long-term drug addict (20 per cent).

But the judge said there would be no credit for remorse. Although McKinley expressed remorse for the hurt and harm his offending caused his family, he completely failed to recognise the harm he caused others.

"What you have failed to recognise and what you have failed to say is sorry to all the other mothers and the families that have been destroyed by the drugs that you put into the community. Where is your apology for that Mr McKinley?

"Where is the apology and remorse for the harm that methamphetamine has done to the communities of Northland?

"And, you've made and sold large quantities of this drug and it has harmed many people," Tomlinson said.

McKinley pleaded guilty in May this year to 16 charges relating to his manufacturing of meth and possession of precursor substances and equipment required to manufacture it; his possession for supply and offers to supply meth, cannabis, and other drugs including LSD and MSDM; and his unlawful possession of firearms and ammunition.

All up he was charged for possessing or offering to supply about 1.1kg of meth, 1.4kg of cannabis, 70 MDMA pills, and 50 tabs of LSD.

He had a 12-gauge semi-automatic shotgun, a semi-automatic .22 Ruger rifle, an AK47, a 50-calibre machine gun and about 1000 live rounds of ammunition.

Tomlinson said it was obvious why drug dealers had guns but for McKinley to have a machine gun was about as serious as these matters get.

Police had also located more than $60,000 cash.

A man targeted during the 2020 police operation Hare had 1000 rounds of ammunition and firearms, including a machine gun. Photo / NZ Police

The sentence was based on a 12-year starting point for the lead manufacturing offences, with two years uplift for the gun offending, six months uplift for McKinley's previous relevant history, including convictions for the same type of offending that resulted in a five-year prison term 14 years ago, and a year's uplift for the other drugs charges.

Counsel Adam Couchman argued against any uplift for the other drugs offending saying it did not add to the criminality of the overall offending but Tomlinson disagreed.

Although Couchman didn't describe it as such, he was essentially saying his client was a supermarket or corner store for all drugs so it did not matter how many different ones he was offering, Tomlinson said.

But his view was that further harm came to the community through the distribution of those other drugs.

"They may have had different markets and different effects but your [McKinley's] willingness to engage in other drugs and put other drugs in the community is worthy of additional condemnation," Tomlinson said.

The Crown sought a minimum non-parole period but Tomlinson said given McKinley's age it was not necessary. He would be eligible for parole as usual - when he had served a third of his sentence (three years, four months).

Nineteen further charges were dismissed in the resolution of the case five months out from a three-week jury trial, which was scheduled for later this year.

One of his co-offenders has already been dealt with by the courts. The other's case is still pending.

- Sarah Curtis, Open Justice