Sniper rifles are radically different from standard hunting rifles. Sniper rifles are “purpose-designed” and “purpose-built” weapons of war. This terminology is used in the firearms literature to describe weapons that are made for a specific narrow purpose, in this case for sniping—highly accurate firing on a target from a significant distance. Jane’s Defence Weekly, for example, draws this distinction very clearly, explaining, “sniper rifles fall into two broad categories: modified versions of standard military or sporting rifles and purpose-designed weapons.”
No single feature marks this special class of purpose-designed and purposebuilt sniper rifles. Rather, the true sniper rifle is an amalgam of specific design features that make it “a bit better in many ways than its off-the-rack cousins to be an overall significantly more accurate weapon,” according to Maj. John L. Plaster (USAR), who is perhaps the preeminent sniper authority writing in the gun press today. “To build a sniper rifle,” observes Adrian Gilbert, another expert writer on the subject, “the manufacturer must use only the finest materials, ensure that tolerances are fined down to a minimum, and impose a draconian level of quality control.”  

Such “purpose-designed” and “purpose-built” sniper rifles are designed and manufactured for the purpose of killing human beings at more than five times the range hunters shoot deer, and to destroy “materiel” targets such as light armored vehicles and aircraft at distances of more than a mile.

The gun industry offers on the civilian market a plethora of military sniper rifles chambered in the civilian equivalent of standard military infantry rounds. Since these calibers are identical to those used in many hunting rifles, it is especially important in some cases to focus on the purpose of the weapon’s design and manufacture.

One of the most popular of these is the .308 Winchester round, the civilian equivalent of the 7.62x51mm round, the standard NATO infantry rifle round from the 1950s to the 1980s. In the early 1980s, NATO followed the U.S. lead and adopted the smaller 5.56x45mm round as its standard infantry rifle round. The smaller round, sold as .223 in the civilian market, was developed for use in assault rifles like the M-16. [red]It has never gained acceptance as a sniping round, because it is generally not believed to have adequate striking power over the long ranges at which snipers operate.[/red]

Some imports from Russia and other former Soviet bloc countries are chambered in a 7.62x54R Soviet infantry round. Some manufacturers and importers offer military sniper rifles chambered in other popular commercial rifle rounds like the .243 Winchester. Older military surplus sniper rifles are also available on the civilian market in a variety of civilian calibers. These include, for example, sniper versions of the M1903 Springfield and M-1 Garand, the U.S. Army’s standard infantry rifles for the First and Second World Wars respectively, in .30-06.