The warning comes after a haul of firearms were stolen from a gun safe in the states north.

NSW Police State Rural Crime Coordinator Detective Inspector Whiteside said police weren't targeting people who had been lax with their firearms, but rather were encouraging people to remain vigilant to prevent what could be a serious incident.

He said often firearms were stolen from properties where people had been away for extended periods of time or were stored next to equipment such as angle grinders, which gave thieves a "free ticket" to breaking into a firearms safe.

"People are still leaving them in their cars, they're leaving them behind the laundry door, and there's easy access to them," Det Insp Whiteside said.

"It's about having firearms closer to where you live and reside to reduce the opportunity for stealing.

"Holistically if you hold a firearms licence, the obligation is to have reasonable precaution to stop them from being stolen or being lost or used by someone who doesn't have a licence to do so."

Det Insp Whiteside said amended regulations for firearms licence holders are not new, and it's important for people to be aware of what is required. 

"The new regulations are not new, they've been with us for 18 months now and it's extremely important that people are aware of them," he said.

"The changes are designed, not to make it harder for farmers or gun licence holders ... it's more about in the wrong hands they become a lethal weapon, and we're trying to prevent those being stolen, so we want people to revisit those firearms changes."

New regulations require licence holders to securely store firearms at their primary residence, or if they are stored in a building or structure outside the home, they need to be within sight from the residence. 

For those unsure of what is require, Detective Inspector Whiteside said talk to local police or visit the firearms registry website.