Ninety-nine guns were taken from alleged gang members and associates by its National Anti-Gangs Squad in 2020-2021, the AFP says.
That is up from 51 firearms seized over the previous 12 months.
More than $3.6 million in suspected crime proceeds was confiscated compared to $1.56 million in 2019-2020, while the 231 charges laid by the squad was a 35 per cent increase.
The firearms haul included concealable loaded handguns and military-grade automatic firearms capable of firing several rounds a second, the AFP says.
“Many of the weapons were found loaded and easily accessible to offenders, increasing the dangers to police and the public,” the agency said in a statement on Saturday.
Sixteen guns including a fully automatic Chinese copy of an AK-47 rifle and a SPAS 12 Gauge shotgun as well as power gel explosives were found at one Perth property during Operation Ironside.
It is suspected they were stockpiled for the Comanchero bikies.
An investigation in NSW into the manufacture and supply of prohibited firearms also resulted in officers seizing two 3D-printed submachine guns and three other firearms.
A further 34 guns and parts were seized during investigations led by the gangs squad between July and October.