Police arrested 37-year-old Bernard Amin Mustafa III last April after getting a tip from a street-level drug dealer.
When they searched his Seattle home, officers found cocaine, fentanyl, methamphetamine, BZP, oxycodone and ecstasy. They also confiscated three guns and more than $300,000 in cash, according to U.S. Attorney Jenny A. Durkan.
At the time of his arrest, prosecutors say Mustafa had a high-powered rifle set in a tripod and aimed out at the front window of the home toward the street.
He also had roughly $200,000 worth of fentanyl, which is an extremely potent pain medication used mostly by cancer patients.
After he was arrested, Mustafa's girlfriend was found dead from a drug overdose. The death is still being investigated, but police say fentanyl was found in her system.
At his Friday sentencing, U.S. District Judge Robert S. Lasnik said Mustafa was a "sophisticated drug dealer with deadly drugs and dangerous weapons," according to prosecutors.