Optics for AR-15

[Chemgeo]

Optics should be selected based on the use case for the rifle, and that basically comes down to target distance. Red dots are fine from 0 to 200 yards, but beyond 200 yards, target ID becomes challenging unless it's bright sunshine on a clear day with nothing in the way and you have excellent vision. For red dots I like aimpoint. The t2 is an industry standard for a reason. Extreme durability, multiple years of battery life, very clear glass. For cheaper options, the duty RDS or the PRO are good options. The compm5 is what I use personally because I like the AAA compatibility

 

At medium range, you can throw a magnifier behind your red dot, or you can go with a fixed prism scope like an acog. The upside of the magnifier is you still have a true 1x optic in your red dot. The downside is it's heavier than the acog and a bit bulky. The acog will have a bit clearer glass, a useful reticle for bullet drop compensation, and be lighter weight and incredibly durable, but wont have a 1x option for close range. A top or side mounted rmr can cover that, but it's not a true replacement for say a t2.

At longer ranges for 5.56, a lot of people are using LPVOs. Good ones are reasonably light compared to a medium power scope like a 3-12, have a 1x that is reasonably close to a red dot, and 6, 8, or even 10x upper ends that allow you to shoot out to 500+ yards fairly easily, all done with holds on a good reticle. But each part of it is a compromise: the 1x is not as good as a red dot, the 6x is not as good as a comparable scope with a larger objective, paralax adjustment, etc. It's a heavy setup, usually north of 26 ounces with the mount. I have used a leupold mk6 1-6, thats the best I've found. I've also used a nightforce nx8 (terrible fisheye, tight eyebox), ATACR (good, but not as clear glass as the mk6, heavier, slightly tighter eyebox), razor genII E (best for the money, close to the mk6). Again they're all compromises.

Thee really is no perfect AR optic, unless you have a very specific use case, which case you can usually find one that is 'really good'. 

Edited June 25, 2022 by Chemgeo

[Ntrain2k]

I have a cheap red dot on mine with a set of the 45 degree flip up iron sites.