A DIVERSE arsenal of military weaponry, including a Sidewinder missile and a rocket launcher, uncovered at an Adelaide home would be extremely dangerous in the wrong hands, police say.

An AIM9 Sidewinder missile, a rocket launcher, six unregistered and two regulated imitation guns, seventeen grenades, four firearm conversion kits and numerous military rounds were found at the home on August 22.

A Modbury North man, 51, was charged with multiple firearms and explosives offences.

Almost all of the weapons were inert or expended, except for the guns and a 20mm explosive round.

SA Police Assistant Commissioner Paul Dickson said it was believed at this stage the charged man was a collector who did not have links to organised crime groups, but investigations were ongoing.

Messenger News reported earlier this month that the Sidewinder missile was among a large cache of weapons seized from the Modbury North home.

Mr Dickson said the fact most of the weapons were inert did not make them completely safe.

"Our concern is that we have ordinance here which can be reasonably easily modified to make it go from inert to not inert so it can be a live weapon," he said.

"If a person is to walk into a bank with a hand grenade and pulled that pin out, you wouldn't know whether it was inert or not.

"This sort of weaponry is not meant to be in our community."

Mr Dickson said possessing such weaponry could also make you a target.

"The issues that we have is that it's highly likely that if you are in possession of illegal firearms that you may be targeted by criminal groups," he said.

"(You could) have those weapons taken from you and then those weapons could quite easily be used by those criminals.

"There is no doubt that weapons like this ... all it needs is a round to be placed into it and it can be used."

Mr Dickson said police were working closely with the military to establish where the weapons may have come from and this investigation was ongoing.

He said the majority of the weapons were 20 to 30 years old.

Originally published as Deadly arsenal found in suburban home