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Trijicon ACOG® 4x32 Army RCO Riflescope - M4

Green Chevron Reticle, Thumbscrew Mount, Tritium / Fiber Optics Illuminated

OVERVIEW

The TA31RCO is an Advanced Combat Optical Gunsight (ACOG) designed for the US Army's M4 weapon system (14.5" barrel). It incorporates dual illumination technology using a combination of fiber optics and self-luminous tritium. This allows the aiming point to always be 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 Corps, the unique reticle pattern provides quick target acquisition at close combat ranges while providing enhanced target identification and hit probability out to 800 meters utilizing the Bullet Drop Compensator. No tools are needed for windage and elevation adjustments because the TA31RCO features external adjusters, making it waterproof up to 11m without the caps. Mounting bosses are integrated into the housing by the eyepiece to allow the easy addition of a Trijicon RMR® (not included).

TA31RCO-M150CP-G reticle image

INCLUDES

    Thumbscrew Flattop Adapter (TA51)
    killFlash Anti-Reflection Device (TA91)
    Objective & Eyepiece Flip Cap Set
    LENSPEN (TA56)
    Lanyard Assembly for Adjuster Caps (TA71E)
    Trijicon Logo Sticker (PR15)
    RCO Manual
    Warranty Card

SKU: TA31RCO-M150CP-G

RETAIL: $1,916.00

FIND A DEALER

The TA31RCO is an Advanced Combat Optical Gunsight (ACOG) designed for the US Army's M4 weapon system (14.5" barrel). It incorporates dual illumination technology using a combination of fiber optics and self-luminous tritium. This allows the aiming point to always be 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 Corps, the unique reticle pattern provides quick target acquisition at close combat ranges while providing enhanced target identification and hit probability out to 800 meters utilizing the Bullet Drop Compensator. No tools are needed for windage and elevation adjustments because the TA31RCO features external adjusters, making it waterproof up to 11m without the caps. Mounting bosses are integrated into the housing by the eyepiece to allow the easy addition of a Trijicon RMR® (not included).

ALWAYS ON, ALWAYS READY

ALWAYS ON, ALWAYS READY

Most ACOG® models are battery free, featuring a tritium/fiber optic illuminated reticle that automatically adjusts the brightness based on available light.

TAKE CONTROL

TAKE CONTROL

Several ACOG models are designed with a user adjustable brightness setting powered by a single AA battery. The 3.5x35 LED and 4x32 LED models both offer six adjustable brightness settings.

RUGGED, RELIABLE HOUSING DESIGN

RUGGED, RELIABLE HOUSING DESIGN

Fixed-power design allows for minimal moving parts to create a nearly indestructible sighting system.

“BOTH EYES OPEN” DESIGN

“BOTH EYES OPEN” DESIGN

“Both eyes open” shooting using Trijicon's Bindon Aiming Concept™ (BAC) feature allows for improved situational awareness.

OUTSTANDING CLARITY

OUTSTANDING CLARITY

The quality of the glass and multi-coated lenses maximize light-gathering capabilities and clear field of view with zero distortion.

EXACT TARGET DISTANCES & HOLDS

EXACT TARGET DISTANCES & HOLDS

Most ACOG models feature a bullet drop compensating and target-ranging reticle for decisive aiming.

COMBAT PROVEN

COMBAT PROVEN

No other magnified optic has been used more in combat than the ACOG.

SHOCK-RESISTANT

SHOCK-RESISTANT

Proven to withstand recoil from a .22LR to a .50BMG and everything in between. Easily passes U.S. Military drop test requirements.

WATERPROOF

WATERPROOF

Exceptional waterproof performance that exceeds military standards. Dry nitrogen-filled to eliminate fogging. This optic is tested to withstand and perform in extreme cold and heat with dry-nitrogen filled housing that mitigates fogging.

INDUSTRY-LEADING RESEARCH, DESIGN & TESTING

We are engineers at heart, like our founder, Glyn Bindon. Therefore, we are bound by a commitment to seek innovative aiming solutions that constantly redefine “brilliant.” This legacy of innovation is fed by what we call The Science of Brilliant®.

LEARN MORE ABOUT THE SCIENCE OF BRILLIANT® 

TESTING PROCEDURES INCLUDE:

Alaska to Africa Tested Immersion Tested Solid Zero Tested Vibration Tested Drop Tested
Length x Width x Height
5.98 in x 2 in x 2.3 in
(151.89mm x 50.8mm x 58.42mm)
Weight
14.9 oz. (422.41g)
Magnification
4x
Objective Size
32mm
Reticle Pattern
Chevron
Day Reticle Color
Green
Night Reticle Color
Green
Bullet Drop Compensating (BDC)
Yes
Caliber
0.223 (14.5 in. barrel)
Illumination Source
Fiber Optics & Tritium
Power Source
Fiber Optics & Tritium
Eye Relief
1.5 in. (38.1mm)
Exit Pupil
0.32 in. (8.13mm)
Field of View (degrees)
Field of View (feet)
36.8 ft. @ 100 yds. (12.27m @ 100m)
Mount
Flattop Thumbscrew Mount (TA51)
Housing Material
Forged Aluminum
Finish
Matte Black
Submersion Depth
-66 ft. (-20m)

ACOG Spec Sheet

Download ACOG Spec Sheet DOWNLOAD

ACOG Reticle Dimensions

Download ACOG Reticle Dimensions DOWNLOAD

ADDITIONAL OPTIONS 3

Trijicon ACOG® 4x32 USMC RCO Riflescope - M4 / M4A1

TA31RCO-M4CP

Red Chevron Reticle, Thumbscrew Mount, Tritium / Fiber Optics Illuminated

Retail: $1,857.00

DETAILS

Trijicon ACOG® 4x32 Army RCO Riflescope - M4

TA31RCO-M150CP

Red Chevron Reticle , Thumbscrew Mount, Tritium / Fiber Optics Illuminated

Retail: $1,916.00

DETAILS

Trijicon ACOG® 4x32 USMC RCO Riflescope - M16A4

TA31RCO-A4CP

Red Chevron Reticle, Thumbscrew Mount, Tritium / Fiber Optics Illuminated

Retail: $1,857.00

DETAILS

COMPATIBLE ACCESSORIES 9

Trijicon ACOG® Flattop Mount for MIL STD Rails

TA51

Retail: $85.00

Trijicon ACOG® H&K Adapter

TA03

Retail: $152.00

Trijicon ACOG® RCO Pouch

TA86

Retail: $55.00

Trijicon® Optical Component Cleaner and Brush by LensPen®

TA56

Retail: $18.00

Trijicon ACOG® Extended Eye Relief Picattiny Rail Adapter w/Colt Knobs

TA77

Retail: $192.00

Trijicon ACOG® Thumb Screw Assembly (RCO)

TA53A

Retail: $22.00

Trijicon ACOG® Thumb Screw for M16/AR15 Models

TA53

Retail: $19.00

Trijicon ACOG® Adapter for Weaver Rails

TA51W

Retail: $95.00

Trijicon ACOG® Extra Screw & Washer Set

TA30

Retail: $13.00

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