She believes there were 170,000 prohibited guns in New Zealand and that "50,000 is not a number to boast about".
McKee said they have always told people to obey the law but that people have floated three reasons to not turn in their weapons.
"Some of them are going to hide their firearms, some of them are protecting history, and some of them - a good portion of them - don't know what's going on," she said.