The scout rifle is a conceptual class of general-purpose rifles defined and promoted by Jeff Cooper in the early 1980s that bears similarities in the design and functionality of guide guns, mountain rifles, and other rifle archetypes, but with more emphasis being placed on comfortable portability and practical accuracy, rather than firepower and long range shooting. Scout rifles are typically bolt-action carbines chambered for .308 Winchester/7.62×51mm, with an overall length of no more than , with a barrel of or shorter, and less than in weight, with both iron and optical sights and fitted with practical slings (such as Ching slings) for shooting and carrying, and capable of reliably hitting man-sized targets out to without telescopic sights. Typically they employ forward-mounted, low-power long-eye relief (LER) scopes or iron sights to afford easy access to the top of the rifle action for rapid manual reloading. Cooper was personally involved with the design work on the Steyr Scout, while other gun manufacturers including Ruger and Savage have since also designed rifles that roughly match Cooper's specifications. Cooper realized that rifles in the late 20th century differed little from those used by celebrated scouts such as Maj. Frederick Russell Burnham one hundred years before, and that advances in metallurgy, optics, and plastics could make the rifle a handy, light instrument "that will do a great many things equally well...". Cooper's scout-rifle concept was largely influenced by the exploits of the scout Burnham in the Western United States and Africa and as such it is best suited to a man operating either alone or in a two or three man team. "The general-purpose rifle will do equally well for all but specialized hunting, as well as for fighting; thus it must be powerful enough to kill any living target of reasonable size. If you insist upon a definition of 'reasonable size', let us introduce an arbitrary mass figure of about ." In 1983 a conference was convened at the Cooper's Gunsite Training Center in Arizona to examine the subject of the modernization of rifle design.