A former college student who turned a sawed-off shotgun on two Montana State University students after becoming enraged over vandalism to his pickup truck was sentenced Friday to 165 years in prison.

District Judge Frank Davis sentenced Brett Byers to 75 years in prison for each murder, plus 15 years for using a gun. The sentences will run consecutively.Gallatin County Attorney Mike Salvagni said Byers, 20, will serve about 40 years before he can be considered for parole.

In imposing the sentence, Davis rejected defense claims that Byers was mentally impaired at the time of the shootings.

Byers was found guilty Jan. 11 of two counts of deliberate homicide in the shotgun slayings of Brian Boeder and James Clevenger, both 19-year-old freshmen.

Boeder and Clevenger were killed a year ago Wednesday when Byers knocked on their dormitory door, entered and fired four rounds at close range from a sawed-off, pistol-grip shotgun.