The weapons included a semi-automatic assault rifle, a similar weapon to the one used in the 1996 Port Arthur massacre, according to Detective Senior Sergeant Joanne Stolp. 

``I cannot think of any reason a person would need to have that weapon,'' she said. 

Police found the guns lying around the man's central Devonport house, including bedrooms and living rooms, during a raid on Monday.

Among the weapons were a .22 calibre magnum pistol, a .22 calibre bolt-action rifle, a 12-gauge under and over shotgun, an air rifle and a crossbow. 

The SKS semi-automatic assault rifle had a bayonet attached. 

Detectives believe the owner, a 30-year-old man, was planning to sell the weapons. 

``To him I think they were purely a commodity,'' Detective Senior Sergeant Stolp said.

Police do not suspect he intended to use the firearms in an attack. 

He told police he found the weapons, and enjoyed collecting guns.

Police allege the man did not have a firearm licence, and that none of the weapons were registered. 

Other people living in the house were not involved in acquiring the firearms, Detective Senior Sergeant Stolp said.

Detectives believe the man also sold methylamphetamine, or ice, and found a quantity of the drug during the search. 

They raided the house after a tip from a member of the public.

Police arrested the man and charged him with selling an unregistered firearm and selling a controlled drug. 

He was bailed to appear at Devonport Magistrates Court on April 29.