C79 optical sight

The C79 Optical sight is a 3.4x28 scope. The sight is not designed as a sniper sight per se, but is rather intended to be mounted on a variety of rifles and to be used by all infantrymen. A tritium-illuminated reticle provides for normal and low-light conditions sighting. The scope itself is Nitrogen-purged to prevent fogging and is covered with an armoured coating of rubber. It can be mounted to a variety of rifles and light machine guns using standard rail mounts. It is manufactured by Elcan and can be found on military service weapons around the world. Its Elcan product name is the SpecterOS3.4x, although in Canadian service, it is typically referred to as the C79 or the C79A2. Similar rifle sights are the SUSAT and the ACOG.

Use

The Elcan C79 is the primary sighting system for the small arms of the Canadian Forces and is mounted on the Diemaco C7 and C7A2 service rifles, the C8 Carbine family, as well as the C9A1 Light Machine Gun. It is also used in the armies of Denmark, the Royal Netherlands Army and Netherlands Marine Corps and Norway.

In Canadian service, all C7A1 and -A2 rifles come equipped with a C79 sight as standard. The C7A1 uses a C79 sight, which is easily distinguished by its dull black rubber overcoating. After reviewing feedback from the soldiers who used the sight, Elcan produced the "fourth generation mount" C79, known as the C79A2, and is mounted onto the overhauled C7A2 rifles, as well as some C8A2 carbines. It was also given a dull green rubber overcoat and the model "C79A2" is etched onto the left hand side of the sight mount.

In Dutch service it is used on the Diemaco C7 and C8, FN MINIMI and FN MAG series of firearms.

Reticle

The reticle of the C79 sight was designed to serve on the C9 Light Machine Gun, thus an appropriate pattern was chosen to aid the gunner in judging distance. The reticle comprises a single vertical post with a sharp tip in the center. The tip is flanked by horizontal Mil-bars on either side. Under the left-hand Mil-bar, a second horizontal bar was added for judging distances.The (radioactive) tritium light source has to be replaced every 8-12 years, since it gradually loses its brightness due to radioactive decay.

Operation

The C79 sight is attached to a mounting rail on the receiver of the weapon. On CF weapons, this is in the form of a modified Weaver rail, also known as a "Diemaco rail". Two adjustment knobs are used to secure the base to the receiver. A bore-sighting device is usually used to roughly zero the sight before a first-time shooter takes it to the range. Adjustments come in 0.25-mil clicks (one click equals 2.5 cm at 100 m or roughly 1 in at 100 yd). Sighting in a C79 sight is normally done at a range of 200 m.
Windage adjustments are made on the left hand side of the base, using a flat object such as a flat-head screwdriver or a coin. Adjustments come in 0.25-mil clicks (one click equals 2.5 cm at 100 m or roughly 1 in at 100 yd). The windage adjustment is intended only for the initial sighting in procedure of the C79.
Elevation adjustments are made via a rotary knob and are adjusted from 200-800m. To bring the sight to a proper elevation zero, a small "gate" must be elevated which disconnects the elevation cam and one mil clicks can now be made. For precise shooting, the gate is usually left open to allow for finer adjustments than the rougher presets. Target shooters will sometimes mark pre-established open gate adjustments with whiteout pens to remind them how many clicks must be made for each range. At close ranges, when rapid aiming is required, the emergency battle sights on top of the sight can be used, although they are very crude and only intended for use inside of 75m.

Variants

C79A2

This model features a green rubber coating and "C79A2" is etched on the left side of the optic. This model is used on C7A2 and some C8A2 rifles. The United States also uses this optic on some of its M4 Carbines.

M 145 Machine Gun Optic

The M145 Machine Gun Optic is a variant of the C79 that was developed for the U.S. Army and is commonly mounted on M240 and M249 machine guns. The M145 is unusual when compared with other optical sights in use with the United States military in that ballistic compensation is in the reticle, rather than in the mount. The reticle is illuminated by a battery-powered LED with varying intensity settings. The mount fits directly to any MIL-STD-1913 Picatinny rail or receiver. Zero is retained despite repeated removal and re-attachment to the weapon. The M145 is extremely resistant to shock and water immersion and has an anti-reflection device and rubber lens caps.

Positives

Despite problems with the mount base, with proper care and maintenance, the C79 is a reliable and durable combat sight. The optical quality of the sight itself is extremely clear and crisp. In low light conditions, the sight does a good job of gathering available light and producing a good picture, with the Tritium providing a readily visible aiming point. The reticle is simple and uncluttered, allowing for more precise aiming than that possible with iron sights. Target identification and assessment is very easy when using the sight out to 400m. Operationally in Afghanistan, the sight has shown its worth at engaging targets out to 300m, where the magnification is appreciated. For closer-in work, some section members will carry EOTech holographic weapon sights or iron sights while the remainder will carry C79A2s for longer-range targets.

Criticisms

While the C79 is generally regarded as having very clean, clear or superior optics, the mounting system has been found to lose its zero under the rough handling commonly encountered in military use. Since the sight itself cannot be adjusted for windage or elevation, they must be done externally, on the mount. This leaves the sight vulnerable to zero shift, since the adjustments occasionally stray from their settings when introduced to sharp impacts, such as the recoil of firing a round, or when the sight is dropped. On the C9 LMG, bursts of fire can even cause the windage screw to unscrew itself. Elcan introduced the fourth generation mount to address these issues. This mounting base uses a tension spring to improve reliability, although it has not permanently solved the problem. The mount continues to be the Achilles heel of the C79, and most users will mount a backup iron sight should the sight fail.

The emergency battle sights on the top of the C79 scope body do not last very long under normal operating conditions. Given that they are made of the same rubber coating covering the sight, they will rub off as a pencil eraser would. Similar emergency battle sights such as those on the SUSAT or ACOG are made from metal and are much more practical. It is hoped that the next version of the C79 will have proper 'irons' on the top.

Users

*AUS
*CAN
*DEN
*NED
*NOR
*USA
**The United States Army uses the M145 Machine Gun Optic on the M249 and M240 Machine Guns. The C79A2 is used on the M4 Carbine.

ee also

*SUSAT - The British Army's equivalent of the C79.
*ACOG - The United States Army's common equivalent of the C79.

References

* Operator’s manual C7 family of combat weapons, Colt Canada 2005-08-17

External links

* [http://www.elcan.com/ELCAN_Business_Areas/Sighting_Systems/Products/Day_Sights/SpecterOS34x.php ELCAN C79 Product Page]
* [http://www.snipercountry.com/InReviews/ELCAN_C79.asp Technical Evaluation: ELCAN C79 scope]