Accuracy
Contrary to popular belief, sniper rifles are not necessarily characterised by exceptional accuracy, especially when compared to civilian sporting rifles, though they nearly always match or exceed the capabilities of other rifles in the military and police categories. A military-issue battle rifle or assault rifle is usually capable of between 3-6 minute of arc (MOA) (1-2 mrad) accuracy. A standard-issue military sniper rifle is typically capable of 0.3-1 mrad (1-3 MOA) accuracy, with a police sniper rifle capable of 0.1-0.5 mrad (0.25-1.5 MOA) accuracy. For comparison, a competition target rifle or benchrest rifle may be capable of accuracy levels up to 0.1 mrad (0.3 MOA).
A 1 MOA (0.3 mrad) extreme spread (meaning the center-to-center distance between the two most distant bullet holes in a shot-group) translates into a variance in the bullet's point of impact of 25 cm at 800 m (about 8 inches at 800 yards), which is considered sufficient to ensure a high probability of hitting a human shape at that distance.
A 2008 United States military market survey for a Precision Sniper Rifle (PSR) calls for 1 MOA (0.3 mrad) extreme vertical spread for all shots in a 5-round group fired at targets at 300, 600, 900, 1200 and 1500 meters, meaning the horizontal spread and hence extreme spread are allowed to exceed 1 MOA, since accuracy is sacrificed in favour of reasonable cost and reliability in harsh environments, as well as ease of operation and maintenance.[6][7] In 2009 a United States Special Operations Command market survey calls for 1 MOA (0.3 mrad) extreme vertical spread for all shots in a 10-round group fired at targets at 300, 600, 900, 1200 and 1500 meters.[8][9] Meanwhile current US Sniper Systems (M24 or M110) do not meet this requirement.
Although accuracy standards for police rifles do not widely exist, they are frequently seen with accuracy levels from 0.2-0.5 mrad (0.5-1.5 MOA)[10]. For typical policing situations an extreme spread accuracy level of 0.3 mrad (1 MOA) is usually all that is required. This is because police typically employ their rifles at very short ranges.[11] At 100 m or less, a rifle with a relatively low accuracy of only 0.3 mrad (1 MOA) should be able to repeatedly hit a 3 cm (1.2 inch) target. A 3 cm diameter target is smaller than the brain stem which is targeted by police snipers for its quick killing effect.[12]
[edit] Maximum effective range
| Cartridge | Maximum effective range[13][14] |
|---|---|
| 5.56x45mm | 300–500 m |
| 7.62x51mm (.308 Winchester) | 800–1,000 m |
| 7.62x54mm R | 800–1,000 m |
| 7 mm Remington Magnum | 900–1,100 m |
| .300 Winchester Magnum | 900–1,200 m |
| .338 Lapua Magnum | 1,300–1,600 m |
| .50 BMG (12.7x99mm NATO) 12.7x108mm (Russian) | 1,500–2,000 m |
| 14.5x114mm | 1,900–2,300 m |
| .408 Chey Tac | > 2,400 m |
Unlike police sniper rifles, military sniper rifles tend to be employed at the greatest possible distances so that range advantages like the increased difficulty to spot and engage the sniper can be exploited. The most popular military sniper rifles (in terms of numbers in service) are chambered for 7.62 mm (0.30 inch) caliber ammunition, such as 7.62x51mm and 7.62x54mm R. Since sniper rifles of this class must compete with several other types of military weapons with similar range, snipers invariably must employ skilled fieldcraft to conceal their position.
The recent trend in specialised military sniper rifles is towards larger calibres that have greater range, such as the anti-personnel .338 Lapua Magnum cartridge and anti-materiel cartridges like the .50 BMG and the 14.5x114mm. This allows snipers to take fewer risks, and spend less time finding concealment when facing enemies that are not equipped with similar weapons.
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