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ACOG Alternative — ELCAN SpecterOS4x Review

Looking for a true military grade combat proven optical sight with a BDC, daylight illuminated reticle, wide FOV and excellent glass at a good price? You should consider ELCAN's fixed 4x SpecterOS4x!

ACOG Alternative — ELCAN SpecterOS4x Review
ELCAN’s SpecterOS4x is a military grade optical sight intended for general issue on combat rifles. It features 4x magnification and a daylight bright illuminated BDC reticle with compensation out to 800m.

When it comes to tough military grade fixed power optical sights the standard by which all are measured is Trijicon’s ACOG. The Advanced Optical Gunsight is a tough and proven design which proved to be a game-changer in combat. It easily provided overmatch to opposing forces iron sighted rifles, providing a huge advantage in being able to identify and engage threats. While the ACOG is very well-known here in the US, ELCAN’s similar SpecterOS4x has not enjoyed the same commercial success. This is a bit of a shame as the SpecterOS4x is a fine military grade fixed magnification optical sight.

The SpecterOS4x is manufactured by Raytheon ELCAN Optical Technologies of Canada. ELCAN itself is an acronym for Ernst Leitz Canada, the founder of the company. One of Germany's premium optical houses, Leitz entered the North American market in 1952 and within two years was producing military optics for the Canadian Government. In the 1970s ELCAN began development of an interesting but heavy 3.5x optical sight intended for general issue on combat rifles. Adopted by the Canadian Army in 1991 this beefy roof prism design put ELCAN on the map. Military sales to the Netherlands, Denmark, Australia, UAE, Kuwait, Brunei and others soon followed. In 1999 the United States adopted a modified ELCAN sight, the M145, for use on M240 and M249 machineguns. ELCAN continued R&D work and developed a novel design, the SpecterDR 1x/4x sight, which was subsequently adopted and is currently fielded by US Special Operations.

The external adjustments help to prevent the ingress of moisture into the tube under harsh conditions. At six inches long and just 18 ounces it’s a compact package.

The success of their SpecterDR 1x/4x sight seems to have cast a shadow on the simpler fixed magnification SpecterOS4x. While it may lack the sex appeal of the dual-magnification SpecterDR, it is an impressive sight in its own right. As its name implies it is a fixed 4x design and it was designed expressly for military use. It has seen success with military sales and was adopted by the British Army as a replacement for the SUSAT sight.

Very business-like in appearance, the SpecterOS4x is not simply a dressed up hunting scope. Rather it is a modern purpose-built military sight in regard to its appearance, design, features and performance. It was specifically designed not only to survive but thrive in an abusive military environment. One trademark ELCAN feature is its external adjustments made in the integral base. This is intended to enhance the integrity of the tube and aids in preventing the ingress of moisture. Compared to previous ELCAN designs the SpecterOS4x features an improved system regarding adjustments and zero retention. The base is designed to mount onto a standard 1913 rail and features A.R.M.S. QD side-levers for easy mounting/removal. Plus durability has been enhanced through the use of an improved alloy.

Unlike traditional designs the SpecterOS4x features an integral base and external adjustments. A.R.M.S. side-levers allow the sight to be easily removed/mounted.

Optically the SpecterOS4x sports a 32mm objective lens which generates a large 8mm exit pupil. Field of view is fairly wide at 6.5 degrees, yet the eye relief is still a healthy 2.75 inches. Adjustments are in .5 MOA clicks and a cartridge case is all that’s required to zero the optic. Once zeroed, all ballistic corrections are made using an illuminated etched glass BDC reticle. Two reticles options are available. The C1 features a central crosshair and a “choke” style rangefinder. The A1 has a chevron with Mil marks on the left and right horizontal stadia. Both enable the rifleman to range a shoulder width target and provide bullet drop compensation out to 800 meters.

These reticles are calibrated to match the trajectory of 5.56x45mm 62 grain M855/C77 ball ammunition fired from a 16 inch barrel. This allows them to be utilized with either a rifle or carbine. The shooter can also choose to illuminate the center of the reticle (for CQB) or the entire reticle (for lowlight). Reticle intensity is bright enough for use in bright sunlight and is night vision compatible. Power is provided by a common DL 1/3N 3 volt battery and runtime is a minimum of 600 hours on the highest intensity. If required a short 1913 rail or a micro red dot sight may be piggybacked on top of the sight. Compact at only 6 inches long, it weighs 18 ounces. Keep in mind the weight includes the integral mount.

A battery box and rheostat is mounted to the left side of the optic. You can choose to illuminate just the center or the entire reticle.

I began testing by checking the SpecterOS4x’s optical performance. Color rendition is accurate being neither warm nor cold. Resolution is also quite good. I could clearly read a street sign 200 yards distant. Plus, resolution didn’t appear to change from the center of the image to the edges in either the vertical or horizontal plane. During testing I detected neither barrel nor pin cushion distortion. I also noted no internal reflections from piercing counter-light. All in all optical performance is very good.

Next I submerged the OS4x in 18 inches of water for 12 hours. There were no leaks so I subjected it to a steam bath for 30 minutes. Again it passed this without issue. So I placed it, still wet, into a freezer for 10 hours. I then removed it and exposed it to another 30 minute steam bath. No issues were encountered.

Following this I zeroed it on a 5.56x45mm AR-15 rifle and fired a control group. I then fired a 10-shot group removing and reinstalling it between each shot. There was no shift in impact. Impressed, I moved to my 600 yard range and put the SpecterOS4x to work engaging steel silhouettes from 200 to 550 yards. Here the Canadian sight performed well providing rapid hits all the way out to 550 yards. Next, I ran it through a variety of drills from 5 to 70 yards. Although slower than a 1x magnification red dot the ELCAN performed well. Keep in mind, the reticle intensity is bright enough to allow you to shoot it with both eyes open using the Binden Aiming Concept. Using this technique the dominant eye focuses on the brightly illuminated reticle while the non-dominant has a full field of view and acquires the target. The brain then superimposes the aiming reticle onto the target. For precision/distant shots you can then shift focus to the magnified image. Properly applied, this technique is very fast and provides rapid hits at close range and precision at longer distances.

Two reticles are offered, the A1 seen here, features a chevron aiming point, Mil marks on the horizontal stadia and bullet drop compensation out to 800m.

I finished testing by putting it to work in low light conditions. Optical performance here was very good but not exceptional. The ELCAN though does have a distinct advantage over the fiber optic/Tritium illuminated ACOG in certain lighting conditions due to its battery powered illumination. If you are in a dimly lit or dark area, such as inside a doorway aiming out into bright sunlight, the ACOG’s reticle is hard to see due to a lack of ambient light to feed the fiber optic. A similar situation is encountered if you are in a lowlight scenario and use a white light. The ELCAN doesn’t suffer from these issues as you can quickly adjust the reticle illumination to fit the environment. Due to this I found the ELCAN SpecterOS4x better suited for lowlight use in conjunction with a white light compared to an ACOG.

Final thoughts? Although not very well-known here in the US, ELCAN’s OS4x is an impressive sight with excellent optics. It’s robust, compact, packed with features, has a daylight visible BDC reticle and yet is priced in-line with its competition. The SpecterOS4x is available directly from ELCAN’s master distributor, Armament Technology Incorporated. Founded in 1988 by Andrew Webber, six times winner of Canada’s prestigious Sniper Rifle Competition, Armament Technology is the primary supplier to Canadian Armed Forces as well as a reliable supplier to NATO and the US military through its distribution network. Despite this they also welcome working with individuals and local dealers. Better still they back up their product with excellent customer service. MSRP of the SpecterOS4x is $1,575 but an online search will turn them up for quite a bit less.

Source: Armament Technology Incorporated; 902-454-6384;


ELCAN SpecterOS4x Specifications

  • Magnification: 4x
  • Field Of View: 6.5 degrees
  • Entrance Pupil Diameter: 32mm
  • Exit Pupil Diameter: 7.8mm
  • Eye Relief: 70mm
  • Reticle: Crosshair or Chevron with BDC compensation
  • Illumination: Daytime visible, NVD compatible
  • Power Source: 3 volt Lithium DL 1/3N
  • Adjustments: External, .5 MOA
  • Elevation Adjustment Range: 120 MOA
  • Windage Adjustment Range: 120 MOA
  • Ballistic Compensation: 200-800m
  • Overall Length: 6 inches
  • Weight: 18 ounces
  • MSRP: $1,575

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