Also seized at the house were drugs, stolen vehicle keys, and items associated with burglaries together with the firearm.
A 21-year-old man was arrested on suspicion of burglary and possession of Class A drugs with intent to supply. He remains in custody for questioning.
Chief Inspector Gary Stuart of GMP’s Trafford Borough, said: “Thanks to the dedicated work of our officers from Trafford and information from the community, we’ve been able to take action like this, which is needed to significantly disrupt criminal activity locally.
“As ever we need your help to do this. Please call your local policing team on 0161 856 7530”.