Outside of Fallujah, Iraq, on September 17, 2004, Sgt. Todd Bowers of the 4th Civil Affairs Group, 1st Marine Expeditionary Force, saw insurgent snipers initiate an ambush on his security patrol. While engaged in the firefight, his sight picture exploded as an enemy bullet impacted Bowers’ Trijicon ACOG.
Fragments of both the bullet and optic showered the left side of his face. A U.S. Navy corpsman tended to Sgt. Bowers and called for a medical evacuation, but Bowers refused and kept fighting alongside Marines during the four-hour battle. The ACOG on his M16A2 was given to him by his father, John, a former Marine sergeant, just two days before his deployment.
Conceived in 1986 as an idea rooted from a halved pair of binoculars by Trijicon’s founder, Glyn Bindon, Bindon moved the roof prism assembly closer to the eyepiece and created a prototype that was light and compact. To make it durable, he selected 7075 aluminum, the same alloy used in making M16 receivers, and forged the housing. He named the concept the “Advanced Combat Optical Gunsight,” and the acronym “ACOG” stuck. The first 4x32mm TA01 featuring a black crosshair reticle was introduced in 1987 with a screw mount for the M16A2 carry handle.
During the U.S. Army trials of the Advanced Combat Rifle (ACR), which was intended to replace the M16 and M4, a test rifle blew up. However, the ACOG remained functional and impressed evaluators. The patent followed news of its durability on February 21, 1989, and a few ACOGs were used during the invasion of Panama (i.e., Operation Just Cause) starting in December that year.
The first military order was for 36 ACOGs in 1991, ahead of Operation Desert Storm, followed by another order from the U.S. Navy SEALs who then began using the 3.5x35mm models. Between 1992 and ’95, the SEALs purchased hundreds more with the added illumination feature of a red fiber-optic reticle. New magnifications were developed and the ACOG was soon adopted by other units including Germany’s GSG9 (1993), the Israeli Special Forces (1996) and by the U.S. Army Special Forces (1998).
Unfortunately, Bindon passed away in September 2003 before he saw his invention’s worldwide approval. In 2004, the U.S. Marine Corps adopted the ACOG as the Rifle Combat Optic (RCO) with the first order for 104,000 4x32mm TA31 ACOGs featuring a bullet-drop compensator (BDC) reticle. Though it took 18 years to sell the first 100,000 ACOGs, it only took 18 months to sell the next 100,000. Then-Major General James Mattis, former commander of the 1st Marine Division, said, “The ACOG mounted on the M16 service rifle has proven to be the biggest improvement in lethality for the Marine infantryman since the introduction of the M1 Garand in World War II.”
The ACOG line experienced growth and developments for various platforms and the second-generation ACOG was introduced in 2015.
I had the opportunity to visit Trijicon’s factory in Wixom, Michigan, where I was trained to build the ACOG. The experience offered unique insight and appreciation for its engineering, the skills of the hands that make them and Trijicon’s quality control. Though my sample, which took several inefficient hours to build, might have been “good enough,” it was laser-engraved with the Guns & Ammo logo so that it couldn’t be sold at retail.
Recently, Trijicon assembled its 1 millionth ACOG and continues to produce more. Visit millionthacog.com to learn more about the ACOG’s history and read stories from those who have relied on it in the field.
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