At least one gang member a day is being charged with firearms offences as police seize ever-larger numbers of guns.
Police are now targeting the supply of firearms to gangs as organised crime groups find new ways to get their hands on guns.
Last year, 402 people on the police's national gang list were charged with a total of 711 firearms offences, most of which were possession.
That is a 54 percent increase in people charged compared with five years ago and a 60 percent increase in the number of charges.
Organised crime unit head detective superintendent Greg Williams said in the first two months of this year, 328 firearms were seized by police including more than a dozen banned military-style semi-automatic weapons.
Just last week, during raids on the Mongols gang in Bay of Plenty, the police seized more semi-automatics including an MP38 submachine gun.
"It's not just the fact they're having them, it's the propensity to use them," Williams said.
"In Bay of Plenty alone, I think there were six instances involving shootings inter-gang from January this year for about a six month period, so absolutely, incredibly dangerous weapons, in the hands of dangerous people."
Williams said gangs had always had guns but they were once used mainly for show.
Now gangs are more likely to use the guns they have, and he puts that down to the arrival of Australian deportees.
To try to stem the flow of guns to gangs, police are changing tack and trying to hit supply chains.
Burglaries are still seen as the number one source but other options are emerging.
Police said a few licenced firearms owners were essentially acting as brokers and some legal guns were being modified.
One example of that, according to Williams, was people turning starting pistols, the ones used at athletics meets, into fully functioning guns.
"We are starting to develop a far better understanding of the illicit supply of firearms in this country," he said.
"Also we have a situation now where people are manufacturing or altering firearms.
"There's a number of situations of starter pistols being bought legally and being modified to fire so we have a far greater understanding of that process."
Police are also monitoring the sale of firearms to gangs.
Illegal guns 'not being handed in'
Williams said it was likely some gun owners did not participate in the buyback and instead sold their guns for more on the black market.
Police are also working with customs to crack down on illegal weapons getting passed border security.
Between 2015 and 2019, Customs seized nearly 3000 firearms, but that included a large haul of 2500 paintball or BB guns in Tauranga in 2016.
Last year, 72 firearms were seized at the border.
Gun Control NZ co-founder Hera Cook said evidence showed illegal gun imports were only a small problem.
"The gun lobby have been telling us that the buy-back's going to achieve nothing because the important guns are the illegal guns, and they're not being handed in," Cook said.
"It's fantastic that the number of guns being brought in by police is going up.
"It shows police are taking action."
Cook said the men who were deported to New Zealand from Australia needed more support upon their arrival, to deter them from joining gangs.
She said it could take years for new firearms laws to have a real impact on gangs.