A neighbour called police on Christopher Michael Gunner, who it will be alleged was on his balcony in Kambah on Tuesday pointing the 80 centimetre long black rifle in various directions while looking through the scope.

The neighbour reported hearing a "click" each time Mr Gunner pointed the gun in a different direction.

Police arrived and cordoned off the property, yelling for Mr Gunner to come out with his hands raised.

The 34-year-old walked onto the balcony with his hands in the air and confirmed he was home with his partner and daughter.

Police will allege they asked Mr Gunner if he had any guns in his possession but he didn't reply.

They allegedly asked if he had anything that could be considered a gun like a water pistol, air rifle or gel blaster, to which he allegedly replied: "I've got a gelly."

Gel blaster guns are made to look realistic and fire water-filled gel blasters.

Police say they found a gun in the kitchen, a fully black rifle labelled "Property of US Government - M4A1 Carbine 5.56mm" and manufacturer "Colt Defence Hartford Conn - USA". The gun was loaded with a magazine.

Police will allege Mr Gunner told them he thought it was legal because he bought it from a shopfront.

Court documents allege he later refused to answer questions and denied knowing anything about what police had seized.

Mr Gunner was arrested and charged with the unlawful possession of a firearm and the carrying or use of a firearm in an improper manner.

Territory firearm laws also apply to replica and imitation guns.

He did not enter pleas.

He appeared in the ACT Magistrates Court on Wednesday where his lawyer Michael Kukulies-Smith applied for bail on his behalf.

Magistrate Louise Taylor granted the man bail on a set of strict conditions, including that he not assault, threaten, harass or intimidate the neighbour who called police, and that he surrender any firearm or any parts of a firearm that he possessed.

He is next due in court in January.