The seller later attempted to contact the buyer – who he had recognised from around town but did not know his name – but the man could not be traced.

Mr Eastman is on trial accused of murdering Colin Winchester in 1989.

Mr Winchester, then the Australian Federal Police Assistant Commissioner, was shot twice in the head while sitting in his car in his neighbour's Deakin driveway on the evening of January 10, 1989.

Mr Eastman has pleaded not guilty.

The trial, in its ninth day on Monday, heard evidence that Mr Eastman had contacted a number of people who had listed guns for sale in The Canberra Times in January 1988.

On February 10, Geoffrey Bradshaw advertised the sale of a .22 Stirling rifle.

He received a phone call from a man who did not leave his name and scheduled an inspection that afternoon.

Mr Bradshaw, from the witness stand, said the buyer had arrived on foot about 1pm, appeared inexperienced around firearms by the way he inspected the rifle, did not haggle over the price, and paid $90 before leaving with the weapon.

Mr Bradshaw said he had included a Nikon telescopic sight, magazine, cleaning kit, and ammunition as part of the deal.

Mr Bradshaw told jurors he had recognised the buyer as a man who had inspected his Chifley home when it had been for sale in about 1979, and also from his time working in a store at Woden Plaza.

The buyer agreed when Mr Bradshaw made the observation, however, the witness said he did not know the man's name.

The court heard Mr Bradshaw had the buyer sign a notice of disposal at the time of sale.

Jurors were shown the document, with the buyer's name signed as JF Thompson, of Atherton Street, Downer.

Mr Bradshaw said, after the sale, he had then been notified by police that he should not have sold the gun to an unlicensed buyer.

He subsequently attempted to track down JF Thompson, however, could not trace the buyer as the name and address did not match.

He said the buyer later called to return the rifle as it had jammed during test firing.

Mr Bradshaw said he had been happy to take back the weapon and other items as he did not want to get in trouble for an illegal sale.

Mr Bradshaw agreed to sell the buyer the scope for $25.

He told the court that the gun and other items had been returned in perfect condition, with only about 20 bullets missing from an ammunition box.

The court heard police contacted Mr Bradshaw in July 1990 and in September accompanied him to Petrie Plaza in an attempt to identify the buyer.

Jurors heard Mr Bradshaw had identified Mr Eastman as the buyer of the rifle.

The court heard the defence did not dispute that the man identified by Mr Bradshaw had been Mr Eastman.

The trial continues on Tuesday.