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Trijicon ACOG® 4x32 BAC USMC RCO Riflescope - M16A4 / M16M4

Red Horseshoe/Dot Reticle, Thumbscrew Mount, Tritium / Fiber Optics Illuminated

OVERVIEW

The TA31RCO-M855 is an Advanced Combat Optical Gunsight (ACOG) designed for either the USMC M16A4 weapon system (20” barrel) or the M16M4 (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 1,000 meters utilizing the Bullet Drop Compensator. No tools are needed for windage and elevation adjustments because the TA31RCO-M855 features external adjusters, making it waterproof up to 11m without the caps.

TA31-D-100581 reticle image

INCLUDES

    Thumbscrew Flattop Adapter (TA51)
    2 Assemblies 1/10 Miliradian External Adjusters
    2 External Adjuster Caps
    Lanyard Assembly for Adjuster Caps (TA71E)
    Scopecoat (TA96)
    LENSPEN (TA56)
    RCO Manual
    Warranty Card

SKU: TA31-D-100581

RETAIL: $1,670.00

FIND A DEALER

The TA31RCO-M855 is an Advanced Combat Optical Gunsight (ACOG) designed for either the USMC M16A4 weapon system (20” barrel) or the M16M4 (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 1,000 meters utilizing the Bullet Drop Compensator. No tools are needed for windage and elevation adjustments because the TA31RCO-M855 features external adjusters, making it waterproof up to 11m without the caps.

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
Horseshoe Dot
Day Reticle Color
Red
Night Reticle Color
Red
Bullet Drop Compensating (BDC)
Yes
Caliber
0.223 (14.5 or 20 in. barrel)
Bindon Aiming Concept™ (BAC)
Yes
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)

ADDITIONAL OPTIONS 9

Trijicon ACOG® 4x32 BAC Riflescope - .223 / 5.56 - BDC

TA31-D-100367

Green Horseshoe/Dot Reticle, Thumbscrew Mount, FDE, Tritium / Fiber Optics Illuminated

Retail: $1,729.00

DETAILS

Trijicon ACOG® 4x32 BAC Riflescope - .223 / 5.56 - BDC

TA31-C-100366

Green Horseshoe/Dot Reticle, Thumbscrew Mount, OD Green, Tritium / Fiber Optics Illuminated

Retail: $1,729.00

DETAILS

Trijicon ACOG® 4x32 BAC Riflescope - .223 / 5.56 - BDC

TA31-D-100365

Green Horseshoe/Dot Reticle, Thumbscrew Mount, Sniper Gray, Tritium / Fiber Optics Illuminated

Retail: $1,729.00

DETAILS

Trijicon ACOG® 4x32 BAC Riflescope - .223 / 5.56 BDC

TA31H-G

Green Horseshoe/Dot, Reticle, Thumbscrew Mount, Tritium / Fiber Optics Illuminated

Retail: $1,617.00

DETAILS

Trijicon ACOG® 4x32 BAC Riflescope - .223 / 5.56 BDC

TA31H-A

Amber Horseshoe/Dot Reticle ,Thumbscrew Mount, Tritium / Fiber Optics Illuminated

Retail: $1,617.00

DETAILS

Trijicon ACOG® 4x32 BAC Riflescope - 6.8 SPC

TA31H-68-G

Green Horseshoe/Dot Reticle , Thumbscrew Mount, Tritium / Fiber Optics Illuminated

Retail: $1,617.00

DETAILS

Trijicon ACOG® 4x32 BAC Riflescope - 6.8 SPC

TA31H-68

Red Horseshoe/Dot Reticle , Thumbscrew Mount,Tritium / Fiber Optics Illuminated

Retail: $1,617.00

DETAILS

Trijicon ACOG® 4x32 BAC Riflescope - .223 / 5.56 BDC

TA31H

Red Horseshoe/Dot Reticle, Thumbscrew Mount,Tritium / Fiber Optics Illuminated

Retail: $1,617.00

DETAILS

COMPATIBLE ACCESSORIES 2

Trijicon ACOG® External Adjuster Caps & Lanyard

TA71E

Retail: $24.00

Trijicon ACOG® 4x32 RCO Modular Anti-Reflection Device

TA91

Retail: $51.00

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