Speaking to Fortune, McKagan said that he decided to educate himself on finance after his pancreas ruptured in 1994.
The rocker enrolled in a finance course at Santa Monica Community College and later began to study at Seattle University's Albers School of Business.
"I'm not a financial planner - I was just trying to figure this out for myself. I didn't want to be 60 years old and broke, having made all this money in my 20s... that was my simple goal," McKagan said.
The former Velvet Revolver member started the firm, Meridian Rock, along with British investor Andy Bottomley to aid other musicians with their finances.