A man is facing multiple charges after a major illegal firearm operation was allegedly uncovered during a raid at his home.

The “clandestine firearm manufacturing bolthole” in the NSW Blue Mountains was uncovered by NSW Police during an investigation into the importation and manufacture of 3D printed firearms and firearm parts, 3D computer aided designed software, and other privately manufactured firearms.

A Blackheath home was raided by detectives at about 8.35am on Wednesday, who allegedly found more than 100 various 3D printed firearm parts including receivers, slides, magazines and triggers.

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“Police also seized two completed firearms — a pistol and longarm, seven imported firearm steel barrels, a box of springs, clips and screws used to complete firearms, and a hard drive with approximately 500 blueprints for the 3D printer to print firearms,” NSW Police said.

The 29-year-old man living at the home was arrested and has now been charged with manufacturing a firearm without a licence or permit, manufacturing a pistol without a licence or permit, possessing digital blueprint for manufacturing of firearms and intentionally importing prohibited tier 2 goods.

He was refused bail and appeared in Penrith Local Court on Thursday.

The NSW Police investigation is ongoing.