Officers were called to reports of trouble at a property in Kingswinford, near Dudley, on September 3, 2019, after a concerned neighbour overheard a man’s voice shout “I will kill you” and a woman screaming “Help me”.
Jonathon Bradley, 52, of Gower Avenue, Kingswinford - described as having "lost it" - admitted offences of possessing a shotgun without a firearms certificate and possessing ammunition without a certificate.
Bradley denied attacking the victim and was convicted of offences of occasioning actual bodily harm and assault by beating following a trial last month at Wolverhampton Crown Court.
Sentencing him on Friday, Judge John Butterfield QC said that the woman had described the shotgun, which belonged to Bradley's, friend in detail and his actions would have left the victim believing that he was about to kill her.
Bradley had brandished the weapon, used for clay pigeon shooting, after the woman scaled a fence to get into the garden after he took away her keys, phone and money following a breakdown in their relationship, which he blamed on a combination of her drinking and his depressive state.
Judge Butterfield said: "Her account of what happened starts and ends with that weapon. It is a marker for her. She was terrified.
"The gun was in the garage. He denied it was at the property. During the first search it was missed by the police, but during a more in-depth search of the garage it was found.
"An examination found it was in good working order."
Judge Butterfield told Bradley: "You took a risk. You had no relevant certificate or licence for a firearm. You should not have had one in your possession or ammunition."
He said that in his judgement Bradley, a "furious man", caused the woman serious distress by pointing a gun to her face.
Bradley claimed that he had the weapon intending to repair it following an outing with the owner.
Judge Butterfield added: "I simply cannot understand why that amount of ammunition needed to be present for you to fix a hinge pin."
But he said that he did not find that Bradley was dangerous.
Mr Richard Hull, defending, conceded that Bradley's reaction to the woman's arrival was "wholly disproportionate".
Bradley previously served in the military background and had post traumatic stress issues, he said.
For the firearms offences and assault Bradley was jailed for a total of five years and seven months, minus time spent on remand following his arrest. He must also pay a victims' surcharge of £181.