The ACOG (Advanced Combat Optical Gunsight) is a series of magnified weapon scopes made by the American company Trijicon. Their scopes commonly offer a magnification of 4x, meaning anything viewed down the scope will be four times bigger than when viewed normally. Usually, ACOG scopes utilise luminescent materials such as Tritium or optical fibers to improve aiming and target acquisition. The ACOG series of weapon scopes is used by the US Armed Forces, as well as parts of other nations' armies such as the British Armed Forces.
"The Advanced Combat Optic Gunsight is a medium speed, medium range scope which magnifies at 4x. A Ballistic reticle makes gauging bullet drop at longer ranges easier."
— Battlelog description
The ACOG was first seen in the Fault Line Gameplay Trailer on an M4 Carbine. It has been remodeled since the reveal, as it now has a red dot in the center of the reticle. The outside of the scope has also been remodeled, with the fiber optic visible on top, and the rear iron sight removed.
In Singleplayer, the ACOG is commonly attached to starting weapons such as the SCAR-H in Operation Guillotine. It can also be found on many weapons dropped throughout the campaign such as the F2000s in Night Shift. It gives the player an advantage of longer range targeting in aiming down the sights, but unfortunately also makes recoil unsuitable for accurate automatic fire.
The ACOG is a 4× scope like its Russian counterpart, the PSO-1. Unlike the default 8x Rifle Scope, the ACOG does not suffer from scope glint and does not need to be steadied but does have noticable sway and recoil compared to low power optics like the Holographic sight.
The ACOG from the Fault Line series of game trailers