RIVERSIDE, Calif. -

A Menifee man who fatally shot his girlfriend in the head during a drunken rage is expected to be sentenced Tuesday to 50 years to life in prison.

      Adam Michael Starkey was convicted April 3 of first-degree murder with a sentence-enhancing gun use allegation and a misdemeanor charge of illegally possessing a firearm for the Jan. 24, 2012, slaying of 38-year-old Jennifer Bowers. Jurors deliberated one day before returning with guilty verdicts.

      According to the District Attorney's Office, the defendant shot Bowers with a .38-caliber Colt revolver while holding the barrel less than two inches from her forehead. The couple had been drinking heavily and squabbling in the hours leading up to the shooting, according to trial testimony.

      Starkey, 32, told sheriff's investigators that at one point he walked out of the single-wide trailer with his pistol and fired all six rounds the Colt could hold into the ground to release his anger.

      Deputy District Attorney Natale Pitre alleged Starkey went back into the trailer moments later, reloaded the gun, then approached Bowers and shot her once at point-blank range.

      Starkey called 911 and reported the shooting. At the time of his arrest, his blood-alcohol level was .23 -- almost three times above the legal limit to drive in California.

      Deputy Public Defender Michael Micallef argued the gun went off accidentally because of mishandling, including from having the wrong type of ammunition loaded into the chamber.

      Starkey and Bowers worked together at a Target store and had been dating for about a year.

      According to court records, the defendant has a misdemeanor conviction for driving under the influence in 2008. One of the terms of his probation was that he not own a gun for a minimum of 10 years.