Rapper T.I. was expected to plead guilty Thursday to federal weapons charges and will face prison time, according to two people familiar with his case.

The 27-year-old singer, whose real name is Clifford Harris, was expected to be sentenced to 1,500 hours of community service talking to youth groups around the country, followed by about 12 months in prison, according to two people familiar with the negotiations who spoke on condition of anonymity because the plea deal had not been finalized yet Thursday morning.

Harris is one of Atlantic Records' most successful artists. His sixth album, "T.I. vs. T.I.P.," was released July 3, debuting at No. 1. He appeared in the 2007 film "American Gangster," which starred Denzel Washington and Russell Crowe.

His prison time could be increased or reduced, depending on his fulfillment of the terms of the deal and good behavior, the two people familiar with the negotiations said. His talks to youth groups are supposed to be about the pitfalls of guns, gangs and drugs.

The U.S. Attorney in Atlanta announced a change-of-plea hearing was scheduled Thursday afternoon at the federal courthouse. Prosecution officials were expected to speak to the media after the hearing.

U.S. District Judge Charles Pannell Jr. must approve the deal.

Harris was arrested Oct. 13, just blocks away and hours before he was to headline the BET Hip-Hop Awards in Atlanta.

He was charged with possession of unregistered machine guns and silencers, as well as possession of firearms by a convicted felon. He faced a maximum of 10 years in prison and a $250,000 fine for each count.

Harris was allegedly trying to buy unregistered machine guns and silencers. He initially pleaded not guilty, and has been under house arrest since he was released on $3 million bond Oct. 26.

Harris, co-CEO of Grand Hustle Records, grew up in Atlanta. His first taste of success came with his 2003 album, "Trap Muzik." In 2004, warrants were issued for his arrest on probation violations for a drug conviction, and he was sentenced to three years behind bars.