ACT leader David Seymour has labelled the gun buyback scheme a waste of time, despite police hailing the first event a success.

Around 440 firearms and accessories were surrendered in Christchurch on Saturday for day one of the two-day hand-in - the first of more than 250 planned around the country. It's designed to rid New Zealand of the kinds of weapons often used by mass shooters, in particular the gunman who opened fire on two Christchurch mosques in February, killing 51.

Nearly 170 firearms owners handed in 224 prohibited firearms and 217 parts and accessories.

But Seymour says the exercise is pointless.

"People who are prepared to line up in the full public glare and hand in their firearms at below-market rates are not the people we should be worried about," he told Newshub.