Sniper rifle

A sniper rifle is a man-portable, high precision, shoulder-fired rifle, for military or law enforcement use, designed to ensure more accurate shooting at longer ranges than other small arms. A typical sniper rifle is built for high levels of accuracy, fitted with a telescopic sight and chambered for a military centerfire cartridge.

The military role of a sniper (a term derived from the snipe, a bird which was difficult to hunt and shoot) dates back to the turn of the 18th century, but the true sniper rifle is a much more recent development. Advances in technology, particularly in telescopic sights, and more accurate manufacturing allowed armies to equip specially trained soldiers with rifles that enabled them to deliver precise shots over greater distances than regular infantry weapons. Some sniper rifles are based on the designs of standard rifles, and some of the most recently designed sniper rifles use semi-automatic fire, for example the M110.

The Whitworth rifle was arguably the first long-range sniper rifle in the world. Designed by Sir Joseph Whitworth, a prominent British engineer, it used twisted hexagonal barrels instead of traditional round rifled barrels, which meant that the projectile did not have to bite into grooves as was done with conventional rifling. His rifle was far more accurate than the Pattern 1853 Enfield, which had shown some weaknesses during the recent Crimean War. At trials in 1857, which tested the accuracy and range of both weapons, Whitworth's design outperformed the Enfield at a rate of about three to one. Also, the Whitworth rifle was able to hit the target at a range of 2,000 yards, whereas the Enfield could only manage it at a distance of 1,400 yards.

During the Crimean War, the first optical sights were designed for fitting onto the rifles. Much of this pioneering work was the brainchild of Colonel D. Davidson, using optical sights produced by Chance Brothers of Birmingham. This allowed a marksman to more accurately observe and target objects at a greater distance than ever before. The telescopic sight, or scope, was originally fixed and could not be adjusted, which therefore limited its range. By the 1870s, the perfection of breech loading magazine rifles led to sniper rifles having "effective accurate" ranges of up to a mile away from its target.

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