Brad was raised in Grand Ledge, Michigan, and graduated from Grand Ledge High School in 2004. He loved bowling, BMX riding, disc golf, fishing, drumming, and riding his Harley. Known for his easygoing nature, Brad brought warmth and energy to everything he did and shared a close bond with his black Labrador, Bill.

He enlisted in the Army in January 2009 and trained as an infantryman at Fort Benning, Georgia. After completing both Airborne School and the Ranger Assessment and Selection Program, he was assigned to Company B, 3rd Battalion, 75th Ranger Regiment as an anti-armor specialist. In mid-2010, he deployed to Kandahar Province, Afghanistan. On August 8, he was killed when an improvised explosive device struck his unit during a mission to clear a fortified enemy position—an act of bravery that helped secure the objective and was later praised as heroic.

His legacy lives on through his family, friends, and fellow soldiers. In 2012, to honor his love of fishing, his family launched the Bradley D. Rappuhn Memorial Bass Tournament. Held each year, the event supports Ranger-focused charities such as the Lead the Way Fund and Operation Homefront.