A Queanbeyan man has been sentenced to more than 11 years in prison after being convicted over the discovery of 276 kilograms of cocaine.

Packets of the drug were hidden in the arm of an excavator and imported from South Africa in June 2019.

Border Force officials and police intercepted the delivery in South Australia after an X-ray revealed 384 packets of the drug, which had a purity of 83 per cent.

They replaced it with a legal substance and sent it on its way with surveillance devices, which led them to Bungendore just outside Canberra.

Timothy Engstrom, 38, was arrested on July 11, 2019 at the landscaping business he owned with his close friend.

The court heard the pair fist-bumped after spending more than two hours using an angle grinder to unload the drugs before their warehouse was stormed by officers.

Engstrom pleaded not guilty to the charge of attempting to possess a commercial quantity of a border control drug, which carries a maximum sentence of life imprisonment, but was convicted by a jury in April.

He was sentenced to 11 years and six months in prison in the New South Wales District Court on Friday.

Justice Gina O'Rourke said Engstrom had been motivated by money and a misguided loyalty to his business partner Adam Hunter.

Hunter is currently serving a prison sentence of 12-years and nine months for the offending. 

Engstrom had told the court he had had the belief that if he "didn't ask any questions, he wouldn't be breaking the law" and did not initially consider himself to be "hurting anyone".

She said Engstrom had "middle responsibility" for his "lesser role" in the offending but now understood his behaviour had been wrong.

Justice O'Rourke said he therefore had a low-level risk of re-offending.

He will be eligible for parole in January 2030, after spending 151 days in pre-sentencing custody.