Trijicon ACOG: America’s Fighting Scope


by Jeff Quinn

photography by Jeff Quinn

January 27th, 2008




I have been using Trijicon’s ACOG scopes for several years now. ACOG stands for Advanced Combat Optical Gunsight, but ACOG could also be an acronym for America’s Combat Optical Gunsight. Living within thirty miles of Fort Campbell, Kentucky, I know many soldiers in the 101st Airborne Division, and a few in the 5th Special Forces group. It is pretty well known that the ACOG is in use by many special fighting units in Afghanistan and Iraq, but there are other optical sights in use there as well. However, soldiers tell me that the ACOG is the one that everyone wants. I also often get inquiries from other military units wanting contact info to purchase ACOGs themselves, without waiting for approval from the suits in DC. My son-in-law has done three tours over there in the sandbox. Not being an officer or senior NCO, he was issued an Aimpoint, but he said that every soldier in his unit that could, traded their Aimpoints for ACOGs. In my opinion, and many others who know better than I agree, the ACOG offers so many advantages in a combat situation that it is just superior to anything else currently available. One very important feature of the ACOG is that it uses no batteries. Unlike many designs, it never needs batteries, and is always “on”. The middle of a firefight is no place to have a battery failure. With the ACOG, that is never a problem. The reticle is lighted at night or in a dark building or cave by a tritium module that is guaranteed for fifteen years to light the reticle. In bright daylight most ACOGs also have a fiber-optic rod that lights the reticle according to available light conditions. This feature self-adjusts, getting brighter as conditions warrant, but dimming for low-light conditions. A reticle that is too bright will blind the user from seeing through the scope, preventing him from seeing the target clearly, if at all. Since the ACOG self-adjusts, the soldier never has to worry about setting the brightness to match the light, or lack thereof. Perfect.

The Bindon Aiming Concept of the ACOG reticle allows the shooter to keep both eyes open at all times, even though the ACOG has magnification that varies from 3.5 to 5.5 power, depending upon the model selected. I was very skeptical of this when I first heard of it, but it works. When swinging the rifle searching an area, the weak eye takes over, allowing for a wide field of view. When the reticle settles upon a target, the eye looking through the scope naturally takes over, due to the magnification.

ACOG scopes are available in many variations, with different reticle colors and styles. I like the very compact size of the smaller ones, but that 5.5 power model has such superb optical clarity, that the tradeoff in size is worth it. I have used one of those on an AR-10 chambered for the .308 Winchester successfully on targets out to 1094 yards (1000 meters for you metric folks). I once believed that much more power is needed to shoot accurately at that distance, but the 5.5 power ACOG handled it beautifully, and the reticle on that scope is marked out to 1200 meters.

The ACOGs are tough, built with a heavy duty housing, the size is kept compact through the use of prisms. The objective lenses are recessed for better protection, and the scopes have plenty of eye relief. These things are built to take the punishment given by fighting soldiers. They are dropped, neglected, drenched, and battered, but hold up very well. They are waterproof to a depth of 100 feet. The adjustment turrets are low and well protected. I won’t go into great detail here about each ACOG, instead I refer you to my previous reviews of various ACOG models (ACOG & Reflex Sight; ACOG with Docter Optic; ACOG 5.5x50mm). All ACOGs will mount on an AR carry handle, and all can use the flattop adapter for mounting atop a Picatinny rail. With an ACOG on the carry handle, the standard AR sights can still be used if needed, without removing the scope. Also, the handle can still be used to carry the weapon.

I have ACOG scopes with a variety of reticles. I made a somewhat inept attempt to take pictures of some of them, and you can view them here, but the reticles on ACOGs that I personally have are better illustrated below:


There are a few other styles, colors, and options available in the reticle choices, and you can get them calibrated for either 5.56mm or 7.62mm NATO cartridges. I am glad that our military is purchasing these for our soldiers. When we send them off to fight for us, they deserve nothing less than the best equipment available. With the large budgets of some of our elite fighting units, they can buy the best scope available. They buy the ACOG.

For a look at the extensive line of ACOG scopes and other Trijicon products, go to

Jeff Quinn







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Click pictures for a larger version.


Trijicon's ACOG: America's Fighting Scope.



ACOGs are compact, reliable and rugged.



Fiber optic lights reticle in daylight conditions.



Adjustments are reliable and well protected.



Author's feeble attempts at photographing the reticles do not do justice to the ACOGs' clarity.



Lenses are solidly mounted and well protected from damage and glare.



Flattop mount allows mounting to Picatinny rails.



Handle mount allows use of iron sights, and retains the handle's intended function.



5.5 power ACOG.