The bill was reported back from select committee last week with a number of recommended changes including some exemptions for a national gun register, more privacy protections, tougher tests to be granted a firearms licence, and having one's first firearms licence expire after five years instead of 10.
The committee largely kept the controversial part of the bill allowing health practitioners to notify police if they think a person's health might make them unfit to use or possess a firearm.
Police would also be obliged to tell doctors about patients who have been granted a firearms licence.
Asked today if his party would support the second reading, Peters was non-committal.
"NZF has been paying close attention to the select committee process and listening to concerns. We will be considering the report and discussing with the caucus and our coalition partner as we consider next steps," he said in a statement.
But Nash said he understood NZ First would support the bill at the second reading, and had no indication otherwise.
"We've been working very constructively with New Zealand First on this."
Prime Minister Jacinda Ardern asked for cross-party support for the bill.
"This is an important part of us trying to ensure that, for instance, gangs and those who do not have the character to possess guns no longer have them.
"I would welcome support from across the House for it."
National Party police spokesman Brett Hudson wanted changes to the bill, including exemptions for pest control and sports shooting, axing the national gun register, and making a conviction for violent, hateful or extremist speech or behaviour a reason to decline a firearms licence application.
Act, the only party to oppose the first round of reforms that outlawed most military-style semi-automatic firearms, is opposed to the bill.