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Trijicon ACOG 4 x 32 Scope USMC Rifle Combat Optic for A4

  • Based on 73 reviews
Condition: New
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$1,336.99 Why this price?

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Availability: Only 5 left in stock, order soon!
Fulfilled by MidwayUSA, Inc.

Arrives Nov 5 – Nov 9
Order within 16 hours and 41 minutes
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Features

  • BATTERY-FREE ILLUMINATION: Features a tritium/fiber optic illuminated reticle that automatically adjusts the brightness based on available light
  • RUGGED ALUMINUM-ALLOY HOUSING: Forged 7075-T6 aircraft-aluminum-alloy housing provides for a nearly indestructible sighting system
  • BOTH EYES OPEN DESIGN: The ACOG can be used as a CQB sight when shooting both eyes open, utilizing the Bindon Aiming Concept
  • COMBAT PROVEN: No other magnifed optic has been used more in combat than the ACOG
  • BULLET DROP COMPENSATING & RANGING RETICLES: The USMC red Chevron ranging reticle allows for bullet drop compensation out to 800 meters designed for the USMC's M16A4 weapon system (20 barrel)

Description

Product description Trijicon TA31RCO-A4CP ACOG 4x32 USMC Rifle Combat Optical Sight for the A4 w/ TA51 Mount Rifle Scope Designed to the exact specifications of the United States Marine Corps, the TA31RCO-A4CP features a red dual illuminated reticle and a unique Rifle Combat Optic reticle pattern that provides quick target acquisition at close combat ranges while providing enhanced target identification and hit probability out to 800 meters. Long- range shots are delivered with greater accuracy thanks to the Bullet Drop Compensator. Coming complete with an ACOG TA51 flattop, Picatinny rail adapter mount with colt style thumbscrews, the scope is designed for use with M16A4 Weapon system (20-inch barrel). The TA31RCO-A4CP incorporates dual illumination technology using a combination of fiber optics and self-luminous tritium with the revolutionary, both-eyes-open Bindon Aiming Concept (BAC),for 'instinctive' target acquisition and increased hit potential. Dual illumination 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. The TA31RCO-A4CP scope is further distinguished by its crystal-clear and distortion-free Broad Band Anti-Reflective Coated Lens, Trijicon fiber optics and self-illuminated tritium phospor lamp for totally battery free operation, and maximum eye-relief and large exit pupil for ease of use. Constructed of military-grade aluminum alloy, the scope is dry nitrogen filled, and waterproof to 100 feet/30 meters. The scope's metal structure and optical system are backed by a lifetime warranty and the tritium lamp is guaranteed to glow for 15 years. The TA31RCO-A4CP Scope comes complete with a Scopecoat to safeguard the scope from dings and scratches, dust, dirt, and moisture in the field and a Lenspen that makes it safe and easy to clean the scope's lens in the field.Features:Trijicon Fiber Optics: Automatically adjusts the brightness level and contrast of the reticle to available light conditions. Bindon Aiming Concept (BAC): Trijicon ACOG models equipped with BAC allow use of the both- eyes-open aiming method along with scope magnification sighting for rapid target acquisition--in any light. Broad Band Anti-Reflective Coated Lenses: Multi-coated lenses provide superior clarity and light gathering capabilities with zero distortion. Trijicon Tritium Phospor Lamp: Aiming reticle glows in low-light conditions for quick target acquisition--with no batteries to fail. Lamp is guaranteed to illuminate for up to 15 years. Internally Adjustable: Since only the prism housing moves, the ACOG is much more rugged than conventional designs. Longer Eye-Relief: Maximum eye-relief for larger caliber rifles and large exit pupil for faster target acquisition. Military-Grade Aluminum Alloy Housing: Forged 7075-T6 aircraft aluminum alloy housing provides for a nearly indestructible sighting system. Waterproof to 100 Feet/30 Meters: Dry nitrogen filled to eliminate fogging. Totally Battery Free: Trijicon ACOG delivers increased hit potential in all lighting conditions--without the use of failure-prone batteries. Specifications:Magnification: 4X Objective Size: 32 millimeters Bullet Drop Compensator: Yes Length: 5.8 inches Weight: 9.9 ounces Illumination source: Fiber Optics and Tritium Reticle Pattern: Chevron with Target Reference System Day/Night Reticle Color: Red Calibration: 0.223 Bindon Aiming Concept: Yes Eye Relief: 1.5 inches Exit Pupil: 8 millimeters Field of View: 7 degrees Field of View @ 100 yards: 36.8 feet Adjustment @ 100 yards: 3 clicks per inch Mount: TA51 (included) Mount on: Flattop Housing Material: forged aluminum Water- resistant to 100 feet What's in the Box? TA31RCO-A4CP Combat Optic (RCO), TA51 Mount, ACOG Thumb Screw (RCO) (TA53A), RCO 4x32 ACOG Pouch (TA86), 4x32 RCO killFLASH, Adjuster Cap Lanyards, 4x32 Scopecoat, Lenspen, Trijicon Logo Sticker, RCO Manual, warranty cardManufacturer Warranty Limited Lifetime: optical systems and metal structure; 15-years: Tritium lampAbout ACOG (Advanced Combat Optical Gunsight) Riflescopes: Trijicon ACOG riflescopes are internally adjustable, compact telescopic sights with tritium illuminated reticle patterns for use in low light or at night. The ACOG's combine traditional, precise distance marksmanship with close-in aiming speed. Designed for use with the M16 family, every feature of the ACOG's mechanical and optical design was chosen for a single purpose: to provide increased hit potential in all lighting conditions--without failure-prone batteries. With a dual-illuminated reticle, the Trijicon ACOG provides shooters with a distinct aiming point in all light conditions--without batteries. Powered by a tritium- phosphor lamp, the gunsight's reticle glows in low-light conditions, while advanced fiber optics automatically adjust the brightness level and contrast of the reticle in brighter light conditions. Broadband, anti-reflective coated lenses provide superior clarity and light gathering capabilities with zero distortion. The ACOG also offers large eye volume, giving you greater leeway-- fore and aft, and from side to side--with which to see through the lens. Of course, once the target is acquired, the ACOG is a trusted ally to help you zero in on a perfect shot. The ACOG is crafted with a tough, military-grade, aluminum-alloy housing and is waterproof to depths of 500 feet--making it nearly indestructible. Only the prism housing moves, so it's much more rugged than conventional designs. And the ACOG does not require failure-prone batteries--so you can rely on it to perform in practically every situation.Bindon Aiming Concept (BAC): Bindon Aiming Concept (BAC) ACOG Riflescopes feature bright daytime reticles using fiber optics, which collect ambient light. This revolutionary, both-eyes-open aiming method provides you with 'instinctive' target acquisition and increased hit potential. And, the scope's ranging is built into many of its reticles, so you only need to set zero once for a multitude of ranging distances.ACOG Scopecoat: The Scopecoat is constructed of the highest quality neoprene laminated with nylon. Its simple design safeguards the scope or sighting system from dings and scratches, dust, dirt, and moisture. Neoprene has 5 percent greater moisture absorbency, which takes moisture (condensation and sweating) away from the scope or sight and helps protect it from rust and corrosion. The nylon laminate shields the scope against the elements. Simply stretch both ends of the Scopecoat over your ACOG sight for optimum field protection.Lenspen: The Lenspen features a safe and easy to use retractable dust removal brush and a special non-liquid cleaning element, designed to never dry out.

Brand: Trijicon


Color: Red


Style: USMC Chevron for A4


Sport: Hunting


Item Weight: 2 Pounds


Material: Fiber Optics & Tritium


Magnification Maximum: 4


Objective Lens Diameter: 40 Millimeters


Magnification Minimum: 3 x


Compatible Devices: Reticle Calibration .223 / .308 / M193 / 300 BLK / 6.8 SPC


Brand: ‎Trijicon


Color: ‎Red


Style: ‎USMC Chevron for A4


Sport: ‎Hunting


Item Weight: ‎2 Pounds


Material: ‎Fiber Optics & Tritium


Magnification Maximum: ‎4


Objective Lens Diameter: ‎40 Millimeters


Magnification Minimum: ‎3 x


Compatible Devices: ‎Reticle Calibration .223 / .308 / M193 / 300 BLK / 6.8 SPC


Mounting Type: ‎A4 w/ TA51 Mount


Night vision: ‎No


Eye Relief: ‎1.5 Inches


Model Name: ‎Trijicon - ACOG 4x32 - USMC for A4 w-TA51 Mount


Manufacturer: ‎Trijicon


UPC: ‎719307302068


Global Trade Identification Number: ‎68


Item Package Dimensions L x W x H: ‎14.4 x 9.4 x 5.2 inches


Package Weight: ‎1.04 Kilograms


Item Dimensions LxWxH: ‎3 x 3 x 15 inches


Brand Name: ‎Trijicon


Warranty Description: ‎See Manufacturer


Suggested Users: ‎unisex-adult


Number of Items: ‎1


Part Number: ‎TA31RCO-A4CP


Included Components: ‎Optic


Date First Available: October 19, 2006


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Nov 5 – Nov 9

This item is non-returnable:

Non-returnable. Transportation of this item is subject to hazardous materials regulation

View our full returns policy here.

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Top Amazon Reviews


  • You get what you pay for.. honestly you do.
I have seen other posts saying that it ain’t authentic or a fake. Well no this is 100% from Trijicon and exactly like the one I had in the service. I love this optic just as much as I loved it back then. Totally recruit proof so do you have to worry about the kid gloves with this thing. Just try not to mess up the glass or use it to open up walnuts and you shouldn’t have to worry about dropping zero on you. Well as long as you have the mount tightened down and just a drop of loc-tight on each screw. Just a lesson learned from the service. So it is easy to zero out and the eye relief is what they say it is. You go to get close to this bad boy so don’t think it is like your hunting rifle scope or what you seen in the “movies” and please don’t even compare it videos games.... please. Really don’t do that. Just walk away you people who want to do that. Just go. So with that said if you are running the old rifleman solid stock on your AR platform you might need to blade more than you wish to get the nose to the charging handle that is taught to us. Or if your wearing body armor.... just putting it out there... just setting it on the table and letting y’all chew on that. So with that said it is more comfortable for us “average” sized guys or maybe a little shorter to have that collapsible stock to get the proper eye relief needed to be in proper position an and still maneuver. As for the PEWPEW nail driver on this thing. It is a darn great optic and a tool to help you see the target better. Shooting fundamentals are up to you this scope can’t fix that. Oh before I forget tape up like 3/4 of the fiber optic tube before using outside in bright daylight. The optic will be so bright it will feel like it burnt a hole straight through your eye. Just a friendly reminder from your friend over here at already done that for you. ... show more
Reviewed in the United States on August 6, 2020 by Christopher Cunningham

  • Just like I remember
I got this acog because it is the exact same one we used in the marines, only its new. Haha. Very nice and sturdy, and the added perk of never needing to replace the batteries. Its my favorite site. Period.
Reviewed in the United States on November 14, 2023 by Christopher Mowery

  • Great scope, a4 reticle works great for 55 grain projects going 3100fps in 100 yard increments
If you shoot a 14.5 or 16” carbine in 100 yard increments (as opposed to meters) then this reticle actually works better than the M4 reticle.
Reviewed in the United States on June 24, 2022 by Napalm113

  • Solid sight.
I was a little concerned of the “CP” designation at the end if the product model number. CP stands for civilian products. Many times the items sold to the civilian market are of lower standards that did not make military sales requirements. I am pleased with the sight I received. I have used the M-16 A-2 at the beginning of my Marine Corps Career and the M-16 A-4 at the end of my career. The rifle expert badge was much easier with the ACOG sight. I have built an A-4 clone with all mil spec parts and an FN barrel. The ACOG finishes the project. After a short sight in the scope was on the money from 100 to 500 yards with M855 ammo. Very happy. I highly recommend this sight. ... show more
Reviewed in the United States on July 5, 2019 by Amazon Customer

  • Just like I was issued in the USMC
This thing is identical to what I was issued in the USMC back in ‘05. Superb quality and clarity. Came in the standard Trijicon “pelican” style case with a cover and manual just like they had in the armory.
Reviewed in the United States on December 1, 2023 by Kent Lander

  • Really deal
This is the real deal, same ACOG that I was issued in the Marine Corps and in the Army. This scope is Marine proof aka basically bombproof. I have been using ACOGs for the last 10 years and trust my life to them, I have no doubt that this one will hold up the same as my issued ones. I had an issue with trying to get it zeroed and sent it to the factory and the customer service was helpful, turned out to be a bad barrel and not the scope. But knowing that it has a lifetime warranty and I can send it in for repairs if something was wrong is nice. The only complaint is I had to pay for shipping, I have other gun-related parts that I have sent back and the other manufactures have paid for the shipping. I know it's only $12, but having paid almost $1,300 for the scope it would be nice if they took care of shipping. ... show more
Reviewed in the United States on March 10, 2020 by Joseph

  • Real Deal
I ordered on 2/4 and received it today. The tritium is lit, the outer coating is rubberized, it has a serial number and came with all the contents it should have. All signs point to an authentic Trijicon TA31RCO-A4. I was 0311 from 2011-2014 and can confirm this is the exact model I used. This thing is the tits. It’s so easy to use, my point man who scored a 35 on his ASVAB mastered it. ... show more
Reviewed in the United States on February 6, 2019 by Zack

  • Pricey, but excellent optic
Very solidly built. Excellent glass, with very clear low light transmission. Reticle is well lit by both the tube and the tritium Both eye open aiming works well, even though this is new for me. Holds zero very well over the first 2 months of use. Although the reticle is well lit, it is small. That's my main quibble. The price must of course be factored into any consideration of cost-effectiveness; essentially, this is a great scope, if you can afford it. ... show more
Reviewed in the United States on November 7, 2011 by P. Stensrud

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