ACOG vs EoTech vs Aimpoint

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One reason to choose a prismatic sight or 1-4x scope is if you have an astigmatism.

1 in 3 people suffer from an astigmatism!

For people with an astigmatism, the nice reticles of an EOTech and an Aimpoint turn into amorphous blobs that vary in size dependent on lighting. I do see a 4 MOA dot in the noon sun, but as the light fades, that dot begins to morph, stretch and distort, as my pupils dilate to compensate for the lower light.

The end result is that these optics are useless to me for anything over 50 yards because their reticle size and point of aim shifts by multiple MOA based on the time of day. Thats why a 1-4x scope or a 1.01x prismatic reflex sight is the best option for me, because etched reticles are not affected by astigmatisms. This is true for 1 in 3 people, statistically.

 

[Zak Smith]

I have astigmatism to a level such that contacts that could correct it to a halfway decent level only became available in the last few years. I still use glasses for most everything including shooting, but use the contacts for moto.

Anyway, I haven't had any problem using a variety of sight systems, ACOGs, Aimpoints, EOTechs, etc.

 

[Z-Michigan]

For people with an astigmatism, the nice reticles of an EOTech and an Aimpoint turn into amorphous blobs that vary in size dependent on lighting. I do see a 4 MOA dot in the noon sun, but as the light fades, that dot begins to morph, stretch and distort, as my pupils dilate to compensate for the lower light.

That's my exact experience with red dot sights - but NOT my experience with the EOTech, which is always as sharp as it gets* regardless of lighting. (The EOTech reticle is made up of about 100 dots of roughly 1/3 MOA each, and if you have good eyesight you can see them individually in dimmer lighting; but it's completely different from the amoeba effect I get with an RDS in dim lighting.)

Anyway, I seem to have an astigmatism since even Aimpoint's an amoeba to me in dim light. I still find them usable in brighter light, but don't like them much for this reason. I stumbled across a 1.5x ACOG and find it just about heavenly for dim light shooting. I would still consider an RDS for action shooting (2 gun/3gun) or if I were supposed to be hanging out of a HMMWV strafing insurgents, which so far is not part of my job or lifestyle.

 

[Zerodefect]

The Aimpoint dots are a blob. Not a dot. Everyone with an Aimpoint is panicking and making appointments with their eye doctors right about now! LOLz.

The ML3 2moa is a nice little "squid of death" at higher settings, for longer ranges I dial it down until it becomes a "jellybean of death".

 

[Bartholomew Roberts]

1 in 3 people suffer from an astigmatism!

1 in 3 people may suffer from astigmatism; but as the comments below yours show, it doesn't mean 1 in 3 people cannot use an Aimpoint or Eotech. If that was the case, the Army would surely have problems since they have hundreds of thousands of sights.

On the Trijicon Reflex, the problem is that, like the ACOGs, it is powered by tritium and ambient light. If you are shooting from an area of low ambient light (from inside a house to outside, from a covered firing line to a brightly lit target, inside a dark room with a weaponlight pointed at the target), then the tritium cannot generate enough light to provide good contrast with the brighter lit target and there isn't enough ambient light for the fiber optic to pick up.

On the ACOG/Accupoint this is rarely* an issue because you have an etched reticle and the reticle just turns black against the brighter lit target, giving you acceptable contrast. The Reflex has no etched reticle. With the Reflex, your reticle will lose contrast and can even disappear entirely.

*The same issue occasionally happens with the ACOG if the ambient light is just bright enough to match the lighting of the target - it usually happens with very fine amber reticles (think TA01NSN at dawn/dusk against a brown cardboard silhouette target). However, it is much more rare because it has to be bright enough to obscure the etched reticle but not brighter than the background lighting.

 

[essayons21]

On the Trijicon Reflex, the problem is that, like the ACOGs, it is powered by tritium and ambient light. If you are shooting from an area of low ambient light (from inside a house to outside, from a covered firing line to a brightly lit target, inside a dark room with a weaponlight pointed at the target), then the tritium cannot generate enough light to provide good contrast with the brighter lit target and there isn't enough ambient light for the fiber optic to pick up.

http://www.trijicon.com/user/parts/products1.cfm?PartID=136

The model I use, the RX01NSN, comes standard with this.

The tritium in Trijicon (say that five times fast) is plenty bright enough to show up on a bright day, and the newer generation devices can last 12-14 hours with no ambient light before dimming. If you are in the dark for longer than that, simply duct tape a mini glow stick to the tritium window.

You are absolutely correct about the contrast issue, especially when shooting at night with a mounted weaponlight. This problem was solved with the polarizing filtered linked to above, something that was demanded by DoD.

On my HD shotgun I went from fiberoptic bead to ghost rings to a CompM4 to the Trijicon Reflex. I by far prefer the Reflex sight picture when looking down a dark hallway lit by a flashlight.

As discussed above, different strokes for different folks. Regardless of what some expert has written, some devices simply won't work for some people, while devices which common wisdom hold "inferior" often will.

 

[Zak Smith]

and the newer generation devices can last 12-14 hours with no ambient light before dimming

Tritium does not "recharge" in daylight. The light it emits comes from radioactive decay.

 

[essayons21]

Tritium does not "recharge" in daylight. The light it emits comes from radioactive decay.

Tritium doesn't emit light. The radiation it emits activates phosphor, usually a zinc sulfide mixture which glows. Light, via fiber-optics, also activates the phosphor, and modern phosphors will glow for 12-14 hours without ambient light before dimming.

The tritium is there so you don't have to leave the scope out in the sunlight for 30mins to fully excite the phosphors.

I didn't think the chemistry was pertinent to the discussion, so I refer to all the magic that happens inside a tritium/phosphor/fiber-optic scope as "tritium."

 

[Bartholomew Roberts]

The model I use, the RX01NSN, comes standard with this.

The issue I've run into when using the RX01NSN is the polarizing filter works by making the screen of the RX01NSN darker so that the reticle has better contrast. Given that the contrast problem only occurs when you are in a darkened area, I didn't care for it since now the sight was too dark to see through without the brightly lit portion - which isn't a huge deal since you can use the sight even with the polarizing filter opaque; but it changes the point of impact since you are now using the BAC technique.

Just not a fan of the Reflex at all. Love my TA11 though. Eyesight can be very quirky from one person to the next, what works well for one user may not work at all for another (red/green colorblind for example).

The tritium in Trijicon (say that five times fast) is plenty bright enough to show up on a bright day

You know, I've got a couple of Trijicon sights and none of them are bright enough to illuminate the reticle on a bright day (or even slightly cloudy day) just using the tritium. All of them need the ambient light from the fiber optics to work. I've never seen a Trijicon sight that was powered by tritium only be bright enough to use in even dawn/dusk conditions.

and the newer generation devices can last 12-14 hours with no ambient light before dimming.

Did you mean 12-14 years? Because that would be about the half-life of tritium - meaning that a sight powered solely by tritium would be about half as bright in 12 years. Otherwise, I don't know what you are talking about above. ETA: Never mind, I see you typed a response to this question while I was typing.

And since we are chatting, there is another statement you made earlier that confused me...

I was fortunate enough to attend a range day with some representatives of Trijicon put on for about a dozen instructors at the NG Marksmanship Training Unit (I am not one). A few hours of instruction and every single person was shooting faster split times with the ACOG than with the M68.

Typically, when I say "split time" I am using that phrase to describe the time from one shot to the next shot. Most commonly, I would compare my split times when doing hammers to my split times firing two aimed shots in rapid succession. So when I hear "split times" I think of a person firing two rapid shots at a target at short range.

In that scenario, I don't see how the sight would make a difference since I am usually just using one sight picture anyway and relying on good position and execution of the fundamentals to put the rest of the rounds on target.

Did I misunderstand how you meant that? Could you describe the actual drill you performed with the M68 and ACOG?

 

[essayons21]

I just took my shotgun with the reflex on it, which has been sitting in a dark closet, with the cover on the site (woops), for at least a month. I took the cover off, took the polarizing filter off, and pointed it out at the bright beautiful day outside and had no problem seeing the dot on a super bright sky from a dark room. Don't really know how to get anymore contrast than that. Maybe its just an issue of eyesight.

As for the drills, I don't remember everything, but it was all standing from the low ready. Times were measured from facing the target, buzzer, shoot. Then facing away from target, turn, shoot. Then same thing with 2 targets, then 3. Then shooting around obstacles, still standing, at unknown number of targets. Times were from buzzer to first shot on target, then last shot on target for multiples. Range was 50m and closer. No pairs, no move and shoot, no positions, nothing fancy. Basically the first block of instruction in Army CRM.

The big surprise was that once you were familiar with the ACOG (TA31), you can acquire the target and get rounds on target just as fast or faster than with the M68. Not sure why, my theory is that it was easier for me to focus on the target and be more confident in my shot with the magnified optic.

 

[Zak Smith]

Between my own tests with a timer and running 3Gun shooters, that is the opposite of the experience I've had with an Aimpoint vs. a TA31/11 and target to target transition times. In my experience the Aimpoint is always quicker in transitions between close-range targets.

 

[Bartholomew Roberts]

I took the cover off, took the polarizing filter off, and pointed it out at the bright beautiful day outside and had no problem seeing the dot on a super bright sky from a dark room. Don't really know how to get anymore contrast than that.

Use electrical or duct tape to cover the fiber optics on the front of the sight, that should give you a good idea of what kind of illumination you'll get from tritium alone (or what the reticle will look like if something obscures the fiber optics).

As for the ACOG, don't know what to say. Like Zak, that is typically the opposite from what I've experienced in my own shooting and watching others shoot and I've owned a TA11 ACOG since about 2002. I like it a great deal; but speed up close is not one of its stronger points in my own personal use.

Just sticking to stationary shooting at static targets scenarios, one issue I have had is that the magnification at closer ranges can lead to target overswing (especially when working left to right rather than right to left).

 

[Z-Michigan]

The big surprise was that once you were familiar with the ACOG (TA31), you can acquire the target and get rounds on target just as fast or faster than with the M68.

In my experience the Aimpoint is always quicker in transitions between close-range targets.

At the moment, I do best in shooting competitions with iron sights, rather than optics. This does NOT prove that iron sights are superior; it only shows that at the current moment, my skill set works best with them. With more practice on a RDS, I would probably find it to be fastest at close range, like most people do.

I think a lot of the decision boils down to whether you want to try what works best for most people and practice til it works with you, or get what you currently think works best for you and just stick with it. Those may be two different options. Which one is right depends on your goals and your time and willingness to train.

 

[Franco]

Thanks all for the advice. I ended up purchasing an Aimpoint CompM4 and love it. Very quick target acquisition at close range and shooting 3" groups at 100yds. The unit is very solidly constructed and simple to operate. Apparently has 80,000 hours of runtime so battery life isn't an issue. Thanks again for your collective input. I find this site to be a very trusted source for my shooting/reloading questions.