Down in the comments of this post, commenter Kevin mentioned ACOGs. That naturally raises the question, “What’s an ACOG?”
ACOG is the acronym for Advanced Combat Optical Gunsight. Trijicon, Inc. has made a line of specialty gunsights for the M-16/M-4 family of weapons for years now. And last year, after using a variety of different products from different manufacturers, the Army settled on the ACOG as the primary sight for the M-4.
Back in the Stone Age, when I was a grunt, all small arms, with the exception of sniper weapons, only had “iron sights.” They were fairly accurate, but took quite a bit of training to master. Further, they were very difficult to use in low light, such as early in the morning and late in the evening. They were of course, next to useless at night.
Traditionally, the Army (and to a lesser extent, the Marines) have been leery of adopting optical gunsights, mostly because of their perceived fragility. The other big factor was that they cost money. Now, in an era when a jet can cost more than the GDP of many small countries, you’d think a few hundred bucks for a scope would not matter. But that’s not how the defense budget works. When the Army only has a limited amount of money to buy stuff, they tend to focus on the big ticket items. Small stuff, like small arms and their accessories, tends to get pushed aside.
One of the consequences of the Army going into Afghanistan and Iraq was that there was a sudden push to make sure our troops had what they really needed in terms of all their gear. That freed up a lot of money for things that otherwise just weren’t going to be bought. Grunts have been watching police and recreational shooters use combat optics on their rifles for nearly 30 years. Not surprisingly, there was a big push to update the Army with combat optics.
Now, a rifle scope is actually not what you really want in most firefights. A scope actually narrows your vision and can even make it harder to see the target. But combat optics use what are called “reflex sights” that are meant to be used with both eyes open. This greatly aids in target acquisition and generally keeping up ones situational awareness.
The first big batch of combat optics was the M68 Close Combat Optic, or CCO. Unlike the crosshairs of a traditional scope, the reticle of a CCO is illuminated, making it easier to see, and far more instinctive to use. There was just a simple red dot. Put the dot on the bad guy, pull the trigger, make the bad guy go away. The CCO didn’t even magnify. It just made it easier and faster to aim. About the only drawback to the CCO is that it takes batteries to illuminate the “death dot”, and grunts already have enough to carry, without having to worry about carrying extra batteries.
Next up, and recently standardized is the M150 RCO (Rifle Combat Optic). This is the Army name for Trijicon’s Advanced Combat Optic Gunsight. The ACOG works along pretty much the same lines as the CCO, but provides some magnification (either 3.5X or 4X) and doesn’t need batteries. It uses radioactive tritium to provide the illumination for the reticle.
Variations of the CCO and the ACOG are also mounted on the M249 SAW and the M240 medium machine gun.