There were no Ray Guns before Buck Rogers! There was no reason for any.

Buck Rogers was an air force officer who fell into a coma and awakened 500 years later in the 25th century. Here he found America in ruins and the world dominated by Mongolians from inland China. He discovered this future world, with anti-gravity belts, rocket pistols, and space ships. He set out to free the world and battle evil and injustice together with Wilma Deering and the scientist Dr. Huer.

Buck Rogers was the first American science fiction comic strip. Published from 1929 until 1967. He has also appeared in comic books, follow up movies, in the 1980s, a television series, and a Buck Rogers radio show that ran four days a week for 15 years. All where enormously popular but not with the quality of the original comic series. The original series was evolved from a story "Armageddon 2419 A.D." by Philip Francis Nowlan, that first appeared in a 1928 issue of Amazing Stories.

Together with H.G. Wells and Jules Verne, it has probably inspired and changed the nature of all the science fiction written thereafter.