Is the Trijicon ACOG TA31RCO truly battery-free?
Yes, it uses fiber optics for daylight and tritium for night, so no batteries are required.
What is the eye relief, and does it affect comfort?
Eye relief is 1.5–2.2 inches; some users find it tight, especially on certain AR stocks.
How durable is this fiber optic riflescope?
Scope is waterproof to 11 meters, shockproof for .308 recoil, and rated for extreme field use.
How does the bullet drop compensator (BDC) work?
BDC is calibrated for 5.56 NATO, enabling accurate shots out to 800 meters with compatible ammo.
Is the illumination level user-adjustable?
No, fiber optics automatically adjust in daylight, and tritium powers up in low-light conditions; no manual settings are needed.
What does the warranty cover on this optic?
Metal and glass: lifetime warranty. Tritium illumination: 15 years from manufacture; replacement is not free.
What mount comes with this model, and is it universal?
Includes TA51 thumbscrew mount, compatible with standard flat-top AR receivers; rings are not required.
Are there known installation or mounting challenges?
Most users find mounting easy, but a correct RMR mount can require clarification with Trijicon for add-ons.