A 9mm submachine gun fired inside a hotel room is among 31 guns seized by police as part of a targeted operation.
Tasmania Police on Wednesday said 20 people had been charged with 64 offences in the past month during the crackdown in the state's north.
The submachine gun was recovered in July after a man, who is facing 15 charges, allegedly tried to evade officers.
The gun was fired inside a Launceston hotel room and was found along with a double barrel 12-gauge shotgun, police said.
No one was injured in the hotel incident.
In a separate search, officers found two guns and stolen power tools at a Deloraine house after an alleged business burglary.
Acting Detective Inspector Jason Jones said every illegal gun in the community was a concern.
"Of those seized in the last few weeks many of the firearms were stolen ... we will continue to remove these items from our streets," he said.
Det Insp Jones reminded people illegal or unregistered guns could be handed to police or licensed dealers without consequence under a permanent amnesty in Tasmania.
A former outlaw motorcycle gang member was charged on Tuesday with gun offences including trafficking and illegally possessing firearms and ammunition.
Police allegedly found a shortened shotgun, pistol, a stolen gun, two gel blasters and ammunition during a search in Burnie.
The 51-year-old man was also charged with breaching a family violence order.
