Trijicon ACOG 4x32 Scope USMC Rifle Combat Optic for the M4, TA51 Mount

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Trijicon ACOG
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The TA31RCO is an Advanced Combat Optical Gunsight (ACOG) designed for the M16M4 weapon system (16" barrel). It provides the shooter with quick target acquisition at close combat ranges while providing enhanced target identification and hit probability out to 800 meters utilizing the Bullet Drop Compensator. The TA31RCO incorporates dual-illumination technology using a combination of fiber optics and self-luminous tritium. This allows the aiming point to be always illuminated without the use of batteries. The Tritium illuminates the aiming point in total darkness, and the fiber-optic self-adjusts reticle brightness during daylight according to ambient light conditions. This allows the operator to keep both eyes open while engaging targets and maintaining maximum situational awareness.
Designed to the exact specifications of the United States Marine Corp, the unique reticle pattern provides the shooter with quick target acquisition at close combat ranges while providing enhanced target identification and hit probability out to 800 meters utilizing the Bullet Drop Compensator
Objective Lens 32 mm
Magnification 4 power
Eye Relief 1.5 in
Exit Pupil 8mm
Field of View 7 degrees (36.8 ft @ 100 meters)
Length 5.8 in
Weight 15.1 oz
Waterproof 66 ft
Tritium 0.1 curies
  • Category : Scopes
  • Magnification : 4x
  • Objective : 32mm
  • Field of View : 36.8 ft @ 100 yds
  • Eye Relief : 1.5"
  • Length : 5.8"
  • Weight : 15.1 oz
  • Finish : Black Matte
  • Reticle : Chevron w/Target Reference System
  • Adj Size : 2 Clicks/Inch @ 100 yds
  • 5
    One of the best on the market

    Posted by Steve A on Mar 7th 2020

    At first I was skeptical about spending this much on a scope. But after I set on top of my rifle at the range I was glad I did. worth every dime!

  • 5
    Battle proven, works for me.

    Posted by John the PMC on Dec 16th 2011

    I've been using the Trijicon ACOG for years as the primary optic on my field rifle. I've seen these things dropped, kicked, knocked into door frames, and submerged in really muddy water and they always do their job. Whether you're in clear daylight with the afghan sun on your face or on a dark street at 3am on patrol, you can see clearly enough to get a head shot at over 600m easy. I prefer these over red dots because you don't need batteries to rely on, and these hold a zero perfect (unlike my old EOTech 551). The only gripe I have or ever hear from anyone else is that the front sight post on our ARs create a blurry dark spot at the bottom of your view. It's not that bad though. And for the OCD people you could always use a riser mount or get a flip up front sight. I plan on using mine for a long time, and the other guys agree, it's well worth the price.

  • 5
    Love This

    Posted by Robert on Nov 15th 2010

    I am in the US Army and have had this optic on my M-4 for the past 3 1/2 years. It is very rugged and is crystal clear. One thing that I would say is that if you are going to get this optic, make sure that you have a folding front sight due to the fact that the A2 style front sight post creates a little blur at the bottom while you look through it. It isn't too bad that you can't fire, but I have noticed it time and time again. The 4 power zoom is perfect for engaging targets out to 800 meters accurately and knowing where your rounds are hitting. I love this optic and wouldn't want anything else on my rifle.

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