His friend, meanwhile, was yelling to McNeilly to "blow her head off, blow them all away".
About an hour later McNeilly and his friend drove to a social gathering where the male victim was, and McNeilly went inside.
"The male victim tried to smooth over his differences with the appellant. After some time, (his friend) became impatient and went inside to speak to the appellant but was told to return to the vehicle. (He) did so, muttering something about firing off a shot," the Court of Appeal said in its ruling released today.
"Within minutes he fired a shot outside the premises. The appellant immediately ran outside and took the shotgun from (his friend), abusing him for his actions. The appellant then took the shotgun into the premises where the male victim and others were. He showed it to them, before leaving."
About 10.30pm, McNeilly phoned his former partner and said "I've just blown a big hole in the floor at his place and your head's next" before driving to the male victim's home and firing a shot at the living room window.
Police found McNeilly with the double-barrelled sawn-off shotgun still in his vehicle about midnight.
In sentencing, Judge Stephen O'Driscoll noted McNeilly had had 48 court appearances in 33 years.
Defence lawyer Anne Stevens argued to the Court of Appeal that the starting point for sentence was too high, the discount for McNeilly's early guilty pleas too low and that there was a disparity between his sentence and that of his friend, who received 2-1/2 years' jail.
Court of Appeal judge Justice Alan MacKenzie said in his finding that the starting point was at the top end, but not outside, the acceptable range.
"That conclusion needs to be reviewed having regard to parity with the co-offender," Justice MacKenzie said.
"We accept Mrs Stevens' submission that a difference of 18 months between the starting points of the two offenders is excessive.
"A combination of starting points near the bottom of the available range for one co-offender, and near the top for the other, has led to an unjustified disparity.
"We consider that a difference of 12 months between the two starting points is a more appropriate reflection of their respective levels of culpability than the difference of 18 months actually adopted."
That, combined with the early guilty plea, led the Court of Appeal to reduce McNeilly's sentence to three years and two months' jail.