Military

Military snipers typically operate in teams, with a spotter focusing on target identification and “doping” the shot and the sniper focusing on operating the rifle. Training will dictate either dialing for elevation and wind, or dialing for elevation and holding off for wind. Both the US Army and USMC seem to be shifting away from traditional mildot reticles toward grid (i.e., Horus) reticle designs in which the sniper holds for elevation and wind. Calibers include 7.62, 300 WM, and recently, longer range .338 calibers. The large 50 BMG rifles are used primarily for anti-material missions and to intimidate the enemy.
The section on long range hunting is also relevant here. Like long range hunters, military snipers require high precision at long range. Military targets are not unlike big game: similar size, camouflaged, averse to direct sun illumination, and difficult to see in marginal lighting. Engagement ranges (500-1,500 m) are similar to long range hunting.

Elevation Adjustment

Read the section on Elevation Adjustment at the end of these quick guides.

First consider scopes with good glare performance and good correction of off-axis aberrations. An upper magnification of 20X or less is recommended. Military snipers using very long range cartridges like .300 WM and .338 LM will want to engage targets from 100 m to 1,500 m and beyond.

Both the US Army and USMC seem to be shifting away from traditional mildot reticles toward Horus reticles that are used with a ballistic computer. A Horus reticle will reduce the internal elevation requirements considerably, but will also place the target further off-axis for both the objective and the erector lenses. Very long range targets (>1,000 m) will incur large bullet drops (>30 MOA). Often the magnification must be reduced to keep such targets in the field of view. Targets therefore appear smaller, requiring better vision acuity on the part of the sniper. Large off-axis images also have worse optical aberrations and glare. Thus for long range targets there is a trade-off with Horus reticles between target range and target visibility.

Select the rings and base, which determines the elevation adjustment requirement (90 MOA for standard rings and 20 MOA base, vs 50 MOA for Burris Signature™ rings using either a dovetail or Weaver base). The use of standard rings will significantly restrict the number of scopes from which to select.

Then select the reticle, turrets and other features from the remaining group of scopes. Micrometer style turrets with good tactile feel that can be operated with gloves are required. A standard eye relief of 3”-3.5” is fine for lower recoiling calibers up to 7.62×51. Heavier recoil calibers may require longer eye relief. Training yourself to hold the rifle firmly against your shoulder is advised.

LEO

Law enforcement officer (LEO) snipers have unique needs for high precision at relatively short range, especially in urban settings. The target’s “vital zone” is 2 inches wide. Snipers usually have ample time to determine target range and make elevation and wind adjustments. Targets use shadow, concealment, defilade, barricade, windows and human shields to protect themselves.  LEO snipers often have only a fleeting moment to acquire the target and make the shot.

LEO calibers include .223, 7mm RM and .308 Win. An upper magnification of 15X or less is recommended. Consider scopes with good glare performance and good correction of off-axis aberrations. Then select the reticle, turrets and other features from the remaining group of scopes. LEO snipers are usually trained to dial both elevation and wind. Their crosshair is always on the intended point of impact when the shot breaks. A simple fine dot crosshair reticle works well for this application. A standard eye relief of 3”-3.5” is fine for lower recoiling calibers up to .308.

With few exceptions, scopes for military and LEO snipers with good optical performance and durability are likely to cost $800+ MAP. The latest turret and reticle designs, better durability, more accurate reticle adjustments, and lower glare will justify higher prices.

Anti-reflection Devices

Contrary to popular belief and practice, honeycomb anti-glare devices (ARDs) provide little safety against detection and actually degrade image contrast. We can all recall movie scenes in which flashes from scope and binocular objectives are as bright as mirrors. These depictions are simply inaccurate. Also, manufacturers use catchy marketing terms like “killflash” to discribe their products. LEO departments are led to believe that these devices solve a common problem. Department armorers typically attach these devices to the riflescope objective and LEO snipers rarely remove them.

On the contrary, LEO snipers are usually in an advantaged position (shaded, elevated, etc.) where reflections of the sun or streetlights do not have a direct path to the target. Anti-reflection coatings on scope objectives are very good, reducing the magnitude of the reflection observed by the target to a miniscule level. Our measurements have shown that the honeycomb aperture pattern significantly degrades image contrast due to diffraction effects, which is detrimental for surveillance, target acquisition and engagement. We recommend not using these devices and instead supplying the sniper with a simple 3-4″ sunshade that can be easily attached in the field if there are bright light sources near the target. Such a device would minimize the chance of a reflection giving away the sniper’s position, as well as improve image contrast by partially obscuring sources of internal glare (see Optics Tutorial).