The WA government says the discovery of a significant amount of high-calibre rifles, firearms and ammunition in a secret bunker under a home in suburban Perth underscores the government's push to "re-write" the state's firearms act.

But pastoralists and firearms traders say they've been blindsided by the government's lack of consultation.

Under the latest iteration of the government's ongoing reforms, high-powered firearms and ammunition designed to be shot over long ranges will be banned from July 1.

The ban covers 56 types of firearms and 19 calibres of ammunition, impacting an estimated 248 licensed firearms and their owners across the state.

The government will buy back the weapons at market value, at an estimated total cost to taxpayers of $1.5 million.

"They're the sorts of guns you can see being used in Ukraine in the war," Premier Mark McGowan said this morning.

"These rifles can fire four kilometres, they can use armour-piercing rounds, and the bullets themselves can go through even armoured vehicles.

Police request

Reform of WA's firearms act was already underway after a looming requirement that gun owners undergo regular mental health checks was announced last week.

The additional action on high calibre firearms came at the request of WA Police after the discovery and seizure of the cache of high powered weapons in Perth.

"Unbelievably, the worst offence this individual has allegedly committed is failing to apply to the local council for approval to build the bunker and underground shooting range," Police Minister Paul Papalia said.

"This person was a licensed firearms owner — most of the weapons down there were licensed.

"Why he needed that many high-powered rifles in a secret underground shooting range is beyond me."

Mr Papalia also rejected suggestions the ban would impact the management of large feral animals, such as camels and donkeys, in remote parts of the state.

"These firearms are not used by professional shooters who cull camels, donkeys or horses, they use a lower-calibre firearm," he said.

"These are powerful firearms that can only be used for hunting animals that we don't have in Western Australia."

Station manager disappointed

Prenti Downs Station manager Jack Carmody said he already spent thousands of dollars a year managing large feral animals on the property, 300km east of Wiluna in the state's far northern Goldfields.

He said access to high-powered firearms would make pest control on his property more effective and achieve better animal welfare outcomes.

"Taking a shot over 300 metres with a .30 calibre takes an extremely skilled marksman, you run a lot of risks at that distance with a .30 cal with bullet drop and wind," he said.

"You could misjudge the distance beyond 300 metres quite easily, which means you're not always going to get a perfect head shot or heart shot."

He dismissed the minister's comments that the firearms weren't required in WA.

"They haven't come to the communities that are having their water sources damaged or destroyed by feral animals, and they haven't seen the animals shot by low calibre firearms," he said.

"They haven't seen the reality, we live it, there has been zero consultation with people such as myself or other shooting and advocacy groups to find out what the practical use of these firearms are."

Control in cities needed

But Geraldton resident Chris Adams said a history of firearms violence in his extended family had highlighted a need for reform.

Having spent a decade managing feral animals in the Pilbara, he said none of the 56 firearms to be banned by the government were needed to control vermin in WA.

But he said there needed to be a focus on firearms storage in suburban areas.

"For everyone to be safe in the city, they need public gun depositories, where you can put your gun in a central base where it is locked tight and secure," Mr Adams said.

"If you have an argument and emotion comes into it, people can lose their state of mind, go for their firearms and kill their partners.

"If [firearms] are not at your address, they're in a public safe, there is time to reason out; that would save a lot of people."

Traders react

Narrogin-based gun trader and WA Firearm Traders Association president, Bevan Steele, said the firearms and agricultural industries had been "blindsided" by the government's announcement.

"There was no announcement, there was no inkling — there's been no consultation in terms of a buyback," Mr Steele said.

He said high calibre weapons weren't used by a large number of farmers but they were critical tools for those who did use them.

"It'd be the same as the government coming and putting a stop on 400 horsepower and above tractors for doing their work," Mr Steele said.

"So while this doesn't [apply] to every farmer or pastoralist, there are some that choose to use these certain firearms."