Divisions have emerged within the Turnbull government as Nationals senators refused to support their own shotgun import ban.
Nationals senators Bridget McKenzie and John 'Wacka' Williams voted with Liberal Democrat David Leyonhjelm in an attempt to overturn the government's import ban on the seven-shot lever action shotgun.
Cabinet ministers Fiona Nash, Matt Canavan and Nigel Scullion abstained from the vote, along with backbencher Barry O'Sullivan.
The attempt to allow the gun to be imported was defeated 45-7 in the Senate on Monday night, with Labor and the Greens supporting the federal government.
Senator McKenzie, a licensed firearm owner, made an impassioned plea to parliament for Australia to have a firearms debate based on science and evidence rather than emotion and fear.
"This debate is just full of so many mistruths," she said.
"People conflate the tragedy of Port Arthur and Lindt Cafe ... increased gun crime on the streets of our cities from illicit firearms ... into a public conversation where law-abiding firearm owners in this nation are derided and belittled by political elites who think they know better."
The split comes amid reports National Party MPs held a fiery meeting over the federal government's direction on Monday, after a by-election recount confirmed the NSW Nationals were ousted by voters in Orange for the first time in almost 70 years.
It also comes as Attorney-General George Brandis was caught raising the idea of de-merging the Liberal and National parties in his home state of Queensland.
He made the suggestion in a conversation with Victorian Liberal party president Michael Kroger at a state council meeting in Ballarat on Sunday during which he spoke of the rise of Pauline Hanson's One Nation - unaware conference organisers had turned on their microphones.
"One Nation, you know their strength is in heartland National party seats and heartland Labor party seats," he told Mr Kroger.
One Nation voted with Senator Leyonhjelm and the Nationals senators to overturn the shotgun ban.
Senator Leyonhjelm insisted neither mass murders nor terrorist attacks would become more likely if the gun was allowed.
He maintains the government promised him the import ban would expire in August if he voted with the government to oppose a Labor amendment to a migration law.
But the government reneged on the deal, reimposing the ban.
"There is a technical term for that, it's what's known as dirty dealing," Senator Leyonhjelm said.
"I wouldn't have voted that way but for the deal."
