A neo-Nazi who fantasised about shooting up a shopping centre has been sentenced to at least four and a half years in jail for weapons and child pornography offences, with a judge pointing to his obsession with "sex, guns and death".

Michael James Holt, 27, pleaded guilty to stockpiling an arsenal of replica pistols, homemade shotguns, slingshots and knuckledusters at his mother's house in Windsor, his grandfather's house in Hobartville and at the Tall Timbers Hotel in Ourimbah.

Michael James Holt with some of the weapons seized.

Police also uncovered child abuse material when they raided the three premises in August 2015 following a tip-off, including sexually explicit conversations with a 14-year-old boy and a 13-year-old girl and naked images that he sent to them.

Judge Jeffrey McLennan spent more than 10 minutes describing the individual weapons and materials found in boxes, fridges, cupboards and garages seized from the three locations. A sheriff began to yawn.