Unless the traveling fair is the explanation, the 1898 date is highly unlikely because of the type of rifle (percussion cap rifles were replaced by bolt-action and/or repeating lever-action rifles like the Winchester in military service by the 1880s, and the belt buckle he's wearing was phased out of US military service by the early 1870s. My personal take on this is that it "feels" like an earlier tintype from the Civil War period (1860-65) or slightly thereafter.