Hornady was the son of John Randolph Hornady and the former Annie Lawton Mulkey. His father, a jeweler, moved to Birmingham in 1873, but relocated to Wilsonville in Shelby County in 1876. Hornady was educated there and returned to Birmingham in 1895 to find work. He started off in a bicycle shop, but soon began composing humorous articles to the Birmingham Age-Herald.
Before long Hornady began working as a full-time reporter for the Birmingham Ledger, and spent the next several years volleying from paper to paper, advancing from reporter to city editor to managing editor. One year he even relocated to Cincinnati to join the Enquirer's editorial staff, but returned to become an associate editor for the Birmingham News.
With the News, Hornady reported on proposals to establish a City Commission to replace the existing Mayor-Alderman form of government, investigating the workings of commissions in other cities and helping shape opinion in favor of the more progressive government through his editorials as well as in public lectures and meetings. He was elected to the body in 1915 and re-elected in 1917 and also served as the vice-president of the five-member board. Hornady's accomplishments on the board included a successful public campaign to increase Jefferson County and Birmingham city property taxes for the benefit of schools. He also lead private fundraising campaigns to benefit schools.
- Hornady, John (1914) The Editorials of J. R. H. Birmingham: Roberts & Son
- Hornady, John R. (1921) The Book of Birmingham. New York: Dodd & Mead
- Hornady, John (1922) Atlanta: Yesterday, Today and Tomorrow. American Cities Book Co.
- Hordady, John (1930) Soldiers of Progress & Industry. New York: Dodd, Mead
- Cruikshank, George H. (1920) History of Birmingham and Its Environs: A Narrative Account of Their Historical Progress, Their People, and Their Principal Interests. 2 volumes. Chicago, Illinois: Lewis Publishing Company.
- Moore, Daniel Decatur (1922) Men of the South: A Work for the Newspaper Reference Library. Southern Biographical Association