Published: Mar 05, 2012 7:15 PM EST
Updated: Mar 05, 2012 9:37 PM EST

FORT MYERS, Fla.- Dylan Wisniewski has been sentenced to 10 and a half years in prison and five years of probation after being found guilty of manslaughter with a firearm in the shooting death of his girlfriend, Ashlee Swayze, in 2010.

In addition, Wisniewski will be required to speak to school-aged children about gun safety once a month, upon his release from prison.

It took the jury less than an hour to deliberate his fate after the three-day trial.

Wisniewski tearfully took the stand to defend himself, but prosecutors argued that Wisniewski was careless and reckless. The defense said he didn't realize the gun was loaded and that Swayze walked in front of the gun.

He faced 30 years behind bars.