It was the tactic of gun lobbyists to "delay, delay, delay", stoke fear, and warn that the 250,000-odd people with a firearms licence would be criminalised by law changes.
He said only 5 per cent of licence holders belong to a gun club, and they were the main ones who would be affected by the bill.
Former cop: Police mismanaged arms control
Earlier Joe Green, chair of Firearms Safety Council of Aotearoa NZ, told the committee that police mismanagement of arms control, due in part to having resources being stretched too thin, was "arguably" responsible for the Christchurch terror attacks.
He cited police documents that he said showed they had put fewer and fewer resources into firearms control, including the year that the accused gunman bought his weapons.
Under questioning Green, who supported the bill, said police suffered from systemic issues that led to those on the front lines "having to do more with less".
National MP Judith Collins said: "Are you seriously telling this committee that the police are the cause of a mass killer going out and killing 50 people?"
Green responded: "I'm not saying the cause, I would use the word contributing factor, the systemic management of arms control and the failure in that are a contributing factor."
When pressed that he said that police were "arguably" the cause in his written submission, Green said he stood by his submission.
Green said he was a police manager for firearms control shortly after the 1996 Thorp Inquiry came out, and he constantly needed to remind management of the need to be vigilant about firearms safety.
Cahill agreed that police had done a poor job, but had improved since the select committee inquiry into firearms in 2016/17.
"It would be fair to say police haven't had a good tack record of managing firearms."
Green also noted that the Thorp Inquiry said that banning MSSAs and assault rifles would not necessarily prevent further mass shootings, but should reduce their frequency and consequences.
He said that the tough sentences in the bill - possession of an MSSA could lead to up to five years' jail - could make an offender think that a shootout with police was "worthwhile", adding that he was not suggesting that offenders thought that way.
Green argued for a two- or three-week public consultation process, instead of the 48 hours that the committee has to receive submission.
Cahill said that collectors were an "obvious risk" in the bill, citing 2010 figures of 19,000 pistols and 9700 restricted weapons that were categorised as collectors' items.
He said the current system of allowing a component to be removed was not ideal as the component could just be put back on. They should be required to be permanently inoperable.
He cited a case where a collector was able to import 74 Uzi sub-machine guns, enough to set up a small militia.
He also said there should not be exemptions for competitive shooting.
"The problem with exemptions is it creates loopholes, and we end up having these firearms in society."
Criminals often steal firearms from legitimate owners, he added.
NZ Antique and Historical Arms Association president Andrew Edgecombe said making collectors' guns permanently inoperable would reduce them to scrap metal.
He said members were being unfairly persecuted because of the actions of the Christchurch shooter.
"They are feeling marginalised, victimised and criminalised ... the future of their interest is now uncertain.
"They have spent their lives collecting, feel persecuted and unfairly targeted ... These guys are really, really hurting. they are most law-abiding people you can imagine."
Committee chair and Labour MP Michael Wood said he owned an antique firearm and didn't feel persecuted, and asked if the association members knew the bill had an exemption for collectors.
"They don't know what's happening," Edgecombe said, but if the 1000 members knew about the exemption, their concerns would be alleviated.
Pistol NZ president Debbie Walker pushed for an exemptions for semi-automatic shotguns and rifles for local, national and international shooting events - under strict conditions.
Walker said an exemption would allow a small, highly-regulated group to compete after undergoing a safety-training regime and receiving a Pistol NZ endorsement.
"This regime is agreed to by customs and police," she told the committee.
Competitors needed firearms licence and could only use such firearms on a certified range, under the control of certified range officer, she said.
The training has to be approved by the Pistol NZ national body, and the competitor has to be interviewed by police.
She said Pistol NZ had about 1000 members who took part in these competitions, and the total number in New Zealand would be well under 10,000.
Cabinet papers released last night show that Cabinet had decided against an exemption to allow would-be banned firearms for international shooting competitions.
However, National MP Chris Bishop said the committee would consider the Pistol NZ submission.
Council of Licenced Firearms Owners spokesman Michael Dowling showed the committee a photo of antique guns with magazine capacity up to 17.
The council has criticised the haste with which the bill is being progressed, and questioned aspects of the bill that may have unintended consequences.
Magazines up to 17 should be allowed, and .22 firearms should be allowed up to 15 cartridges for practical and economic reasons, he said.
He supported allowing semi-automatic shotguns with capacity for seven rounds.
Hunting & Fishing chief executive Darren Jacobs also supported this, noting it was common for sporting semi-automatic shotguns for sporting purposes to have seven-round capacity.
He said he supported the bill, but warned that a blanket ban would impact hunters.
Jacobs said a five-cartridge limit for semi-automatic shotguns was suitable for hunting, but not practical for a buyback scheme, as hunters would hand in their seven-capacity shotguns and then buy a five-capacity one.
"We don't see any major shift in public safety by going to seven."
Andrew Gilchrist, who was the chief of staff for the Australian Minister of Police after the 1996 Port Arthur massacre, said the buyback scheme in New South Wales worked much better once police took trucks into the community to collect the guns.
He warned that there were often emotional scenes from widows or family members who handing in firearms that had belonged to a loved one who had passed away, and it would prudent to have services at those collection points.
He said there were cases of corruption in the buyback scheme as well, including unlawful sales practices. The industry actually flourished afterwards, having had an injection of $500 million in 12 months from the buyback scheme.
The New Zealand Government is still working through the details of the buyback scheme, and it estimates it may cost up to $200 million - though it may end up being much higher.
Ban MSSAs: Fish & Game
Fish & Game chief executive Martin Taylor told the committee he supported the bill, and that MSSAs should be banned.
"MSSAs have no place in NZ and never should have been allowed in the first place."
Taylor questioned whether an amnesty until the end of September would be long enough; Cabinet papers released last night showed that Cabinet did consider an amnesty until the end of December this year.
Taylor said some sporting semi-automatic shotguns with capacity for six or seven rounds would be banned in the bill, and said a two-year amnesty would allow hunters to use these guns for the 2019 and 2020 season.
He added that a permanent change to these guns to a five-round capacity would only cost about $200, and should be paid for by the Government as a much cheaper alternative to buying them back.
There were up to 15,000 such semi-automatic shotguns, and this move would save the Government up to $30 million.
Aramoana cop: We need a national firearms register
Ex-cop Tim Ashton, who shot Aramoana killer David Gray, said the bill was a good step but there needed to be a national firearms register.
"The same weapons used by David Gray are still for sale ... They are in the hands of the criminal community, and we don't know how many."
"We have a duty to make New Zealand safer. These weapons have no place in our society."
Airsoft NZ spokesman Ben Allen said the bill might unintentionally capture parts that make up airsoft and paintball guns, which he said fire 6mm plastic balls and cannot be modified.
The committee welcomed Allen's submission and assured him the bill would be cleaned up.
Competitive shooter and campaigner for tougher sentencing of firearm offenders Mike Loder told the committee the bill was "rushed and ill-thought".
"Bad laws make things worse, they can drive firearms underground and make the nation less safe."
He said police should not manage the Arms Act and listed a number of allegations that he said showed police incompetence, such as losing "25,000 shooters down the back of the couch".
He added that police negligence had contributed to allowing Australians with gun convictions into New Zealand, who then acquired firearms licences.
"When we talk about gun control, criminal always have access to firearms. Whether or not they use them is up to us."
Committee members questioned Loder's reasonableness, noting inflammatory statements on his blog and that he has called politicians and gun safety advocates "tyrants" and "scumbags", and had tried to link firearms control with Nazi Germany.
Loder said he was not a conspiracy theorist, and disarming the Jewish people in Germany had contributed to the rise of the Nazis.
Collins asked Loder: "Do you consider you are a fit and proper person to hold a firearms licence?"
Loder said he was as harming a person had never occurred to him.
After his submission, Collins said: "That gives us a little perspective, I think."
Submissions will continue to be heard all day.
