After graduating from college, he spent four years as an officer in the United States Air Force, where he received training as a disaster preparedness officer at Strategic Air Command base. David also served one year at a remote site in Alaska and received advanced survival training there. Following military service, David spent 9 years as a Multnomah County Deputy Sheriff, transferred to Portland, where he spent 9 years as a Portland Police street officer, and ended his career with 14 years as a crime scene investigator. He also has a legal background, having worked for 5 years as a deputy district attorney.

David has been reloading his own ammunition for over fifty years, including rifle, handgun, and, recently, shotgun ammunition.