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 utilize 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.
— 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.
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 the magnified recoil makes it 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 noticeable sway and recoil compared to low power optics like the Holographic sight. Due to this, the ACOG is most effectively used on weapons with a Bipod, prone at medium to close range, or guns with low recoil. However, burst-firing or single shots can greatly help the recoil issue, along with a player-by-player basis of recoil control using the joysticks/mouse.
— Battlelog description
The ACOG is unlocked for American and European primary weapons through progression and is unlocked through Battlepacks for all other primary weapons. It is the first optic unlocked for American DMRs, requiring only ten kills.
The ACOG (4x) appears in Battlefield Hardline as a primary weapon optic. Unlike previous Battlefield games, the ACOG now uses a small red ring as its reticle.
- The ACOG model in the Fault Line trailers was ported from Medal of Honor 2010's multiplayer. While this was likely a placeholder model, the GUI icons of the ACOG still depict the old model.
- The ACOG diffuse textures still feature elements from the old MOH2010 model, such as elements of the backup ironsights. This is also present in Battlefield 4's ACOG textures.
- When the ACOG is not aimed, the chevron can still be seen. This is most notable when the weapon is centered with the bipod.
- The ACOG reticle (like most others) lacks range finding details. The horizontal lines on a real ACOG will represent roughly the shoulder width of a man at respective ranges, shown here.
- For some reason, the ACOG in the Battlelog icon has a blue fiber optic. In gameplay, the fiber optic is red. However, in the options menu, the player can set the reticle for optics to a blue colour if they wish.
- The left side of the ACOG shows text saying "MARINES" along with a serial number of 100545-210305. The number 73 is also present on the model, likely an inventory identification number.