Two men aged 28 and 30 have been charged with possession of a firearm in suspicious circumstances and possession of ammunition in suspicious circumstances.
Both are expected to appear at Lisburn Magistrates court on November 5.
The pair were arrested in the Tonagh Drive area of Lisburn on Saturday.
Two men were seen to be acting suspiciously in Tonagh Drive on Saturday, and when they were stopped a suspected firearm was recovered from their possession.
Detective Inspector Cummings said: “The weapon will be submitted for forensic examination.”