Jack C. Altsman, 43, of Beaver Falls, received the mandatory sentence from U.S. District Judge Terrence McVerry.
McVerry said he had "great difficulty" in imposing the mandatory sentence after Altsman said he didn't realize hunting was illegal for him.
"I wasn't in a bank with an automatic weapon. I wasn't carjacking someone ... I wasn't in a bar with a gun," Altsman said. "I was hunting."
Prosecutors said Altsman had two felony burglary convictions before he was seen by deputy state game commissioners hunting on property he owned in Hovey Township on Nov. 26, 2001.
Altsman had pleaded guilty in November to possession of a firearm by a convicted felon. He said he didn't challenge the charges for fear that he would spend more time in prison if he was convicted at trial.
Under the guidelines, a sentence of at least 15 years was mandatory.