Chapel was born in Manchester, Iowa on 16 May 1904. He studied at the University of Missouri and later at the Naval Academy in Annapolis.He saw active service in Panama, Cuba, Nicaragua, Phillipines, and China. He was discharged in 1937 after being wounded.
Chapel wrote about a variety of subjects such as aviation and forensics, as well as firearms. The exact number of articles is not known, but could be as high as several thousand, including 3,000 for Hobbies Magazine.
After his military career, he worked as an aeronautical engineer at Northrop Aeronautical Institute in California, and wrote or helped edit many of the technical manuals for the industry. He also wrote several articles on ballistics and fingerprinting for the police.
Chapel was active in several organizations, including the NRA and the Veterans of Foreign Wars.Based on a pro-gun stance, Chapel entered Republican politics in 1950, being elected to the California state legislature. He remained in politics until 1966.
Although he wrote articles on a variety of subjects, most of his books were about firearms, starting with Gun Collecting in 1939. His 1940 book, The Gun Collector's Handbook of Values was one of the first to provide values for non-professionals, and he contributed to later editions for many years. From the 40s until his death, he at least nine books on gun topics.
His most well known book, Guns of the Old West, is considered a standard reference for Western firearms studies.