Description
The Trijicon ACOG (model 100308 / TA31-D) is a battle-proven fixed-magnification combat riflescope purpose-built around the .223 Remington / 5.56x45mm NATO cartridge. Part of Trijicon’s Advanced Combat Optical Gunsight (ACOG) family, this TA31-D variant ships in a distinctive Sniper Gray finish on a forged aluminum housing, giving it the ruggedness and reduced signature demanded by elite military and law-enforcement users.
At the core of this optic is a fixed 4x magnification paired with a 32mm objective, producing a 36.8 ft @ 100 yd field of view and a generous 1.5″ eye relief. The optic features Trijicon’s signature Dual Illuminated Red Chevron .223/5.56 BDC reticle, which combines fiber-optic daylight illumination with tritium for low-light, no-battery operation. The chevron aiming point is designed to be zeroed using the tip at 100 meters, with the bullet-drop-compensating reticle providing hold points out to 800 meters for both .223 Rem and 5.56 NATO loads.
Multi-coated lenses deliver a sharp, high-contrast sight picture across the full field of view. The housing is built to survive hard use: it is fogproof, shockproof, and waterproof, and the windage and elevation adjustments click in precise .25 MOA @ 100 yd increments. This 4×32 ACOG measures just 5.8″ long, making it an ideal balance of speed, durability, and compact size for a tactical carbine or rifle.
This listing includes the ACOG optic and the TA51 mount, ready to drop onto a flattop upper. As with all Trijicon ACOGs, the illumination source requires no batteries – the fiber-optic collector harvests ambient light by day and tritium takes over in darkness, so the reticle is always available when you need it.
