AR Optics Theory

[Hueco]

I'm setting up my first mid length AR15, having previously built a DMR. This one is a 14.5" that I intend to use as a general, multipurpose AR. It'll be staged in case it's ever needed at home and it'll get used for 2-Gun and 3-Gun games on the weekends.

As I round out this build, I'm torn on optics choices. The only similar type rifle I've got is a .22LR 10/22 with a Vortex Strikefire that I use for speed steel. I do quite like that dot but am also limited in experience.

Looking at AR optics, I'm blown away with seemingly endless options...
- Red dot or holographic?
- Prism sights?
- LPVO
- Magnifiers
- If using any combo of magnifier/dot/holo...use backup irons? Or maybe a backup rear and fixed front post? Lower 1/3rd co-witness vs. absolute?

Too.Many.Choices.

What I'd like to learn to help whittle things down is some of the "theory" behind the optics choice. What have you done for a similar set-up and why? What would you avoid?

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[arakboss]

This chap believes in minimalist optics.

 

[ZA_Survivalist]

This chap believes in minimalist optics.

View attachment 1070882

And look at his terrible trigger discipline.

 

[Member 34319]

My theory is usually KISS. That and weight.

Keep it simple, and keep it light.

 

[308]

Since you stated you have a DMR, as do I, I will comment on my experience and preference for <50 yard shooting. All the sights mentioned, I have in my possession and are currently mounted.

First Choice:
Eotech because when quickly attempting to get on target while shooting out steel plates, my eyes focus better on covering the plate with the 65moa circle while knowing the small center dot will naturally be centered on target.

Second Choice:
Trijicon MRO because it is compact, rugged and the reticle brightness can be adjusted as required. It also has the NV mode for NODS. Downside is it takes me longer to quickly acquire the red dot while sweeping to the next steel plate.

Third Choice:
Trijicon Reflex because I've had it for 20yrs and it still functions fine and has a bright self illuminating dot. Same visual issues as the MRO, at least for me.

Fourth Choice:
Aimpoint 9000L because I've had it for a long time and it always works. On/Off switch is awesome. It is a bit too long for my preference. Same visual issues as the MRO and Reflex.

Bottom line; I would choose the Eotech and MRO over all others. My $0.02

 

[Lasers]

Heuco, I need to head out to North Fork to sight in a few things, lmk if you want to coordinate.

I have an LPVO setup AR
I have a Eotech setup AR
I have a holosun green setup AR

Both the holosun and eotech have flip magnifiers behind them too.

 

[Aero Denezol]

My theory is usually KISS. That and weight.

Keep it simple, and keep it light.

^^^Yes

My favorite is the PA ACSS Cyclops (1x) absolute cowitness with irons using a 50/200 zero. Small optic, no magnification.

 

[osprey]

Hard to go wrong with a 1x prism. Easy to acquire targets with both eyes open and has etched reticle so even when batts fail it still can be used effectively.

 

[PDX_Schmoogle]

My current main build is a 14.5in with an ELCAN 1x/4x. I run this build suppressed (SilencerCo Saker 556K) or unsuppressed. I'm a little torn on what to say about it, so I guess I'll just kind dump some thoughts:

I find myself torn between what optic is 'the best' for what I'm trying to do, and over time I have handled a lot of different optics varying in quality and capabilities. I think that realistically it would be quite difficult to justify shooting anybody beyond 100yd, so perhaps magnification isn't really necessary. Then again, it's really nice to have at times... I settled on the ELCAN because I was able to get it for a killer price, and on paper it seemed to check a ton of boxes. I guess when I think of a realistic home defense scenario, if it's an immediate 'bump in the night' threat, I am grabbing the Glock to clear the house. No rifle will ever beat the mobility of a handgun indoors. If I am going to run around outside then I'm grabbing the rifle, in which case I think magnification would be a huge help, being that we live in the countryside.

Things I love about the ELCAN:
- Of all the LPVO optics I've looked through, the 1x setting on the ELCAN is one of the best. The red dot setting is Aimpoint levels of bright and clear, glass quality is incredible.
- The 4x setting is fantastic as well and has a huge FOV. It's nearly the same as an ACOG at the 4x setting, which if you've ever had a chance to use one of those you'll know how amazing they are.
- Switching between the 1x and 4x setting using that snappy lever is freakin cool, the mechanism really inspires tactile confidence in what setting you chose.
- The entire optic body is much shorter than an LPVO.
- Build quality is insane, it's built like a tank. I am very confident that it will never break, and it has a track record much like the ACOG.

My complaints with the ELCAN:
- It's pretty heavy, weighing in at about 24oz. That being said, a quality LPVO with a quality mount and throw lever is actually not much different. I pondered whether an ACOG with an offset red dot could be lighter still, but at least on paper that doesn't really seem to be the case.
- The eye box is also somewhat short, meaning you need to dial in your stock length and optic position to get it just right. I found that the optic works best if you put it as far back on your pic rail as possible, then adjust the stock until the eye box is exactly where it should be when you pull the gun up.
- The back up irons are effectively worthless. They are so short and so close to your eyes it basically just doesn't register.
- The cost is substantial, unless you get lucky. That being said... You get what your pay for.

So idk. I think it really depends on your budget and what you prioritize. Personally, after being spoiled by high end glass, I am prioritizing quality above all else. If I have $700 to spend on an optic I am well aware that a $700 red dot is super nice, while a $700 LPVO with a mount and lever is pretty much entry level, so in that instance I would take the $700 red dot. If I have decided that I need magnification, then I will save up for a high end option for that magnification.
Something I've noticed is that, in general, magnification costs you weight. No way around that. Glass lenses and optic bodies are heavy no matter who makes them. Red dots will always be lighter and faster. As you define what you want the build to be capable of, I think the answer will become clear as to whether red dot or magnified make sense.

 

[clanhanson]

If primary focus is close work but occasional distance, red dot or holo with magnifier. If focus is medium to long range with decent usability close, LPVO or prism with red dot piggybacked or offset. I dislike LPVOs because of weight, limited eyebox, and big center of gravity shift. I'm a prism fan.

 

[monkeybutler]

I like big eye boxes and generous eye relief. Some extra weight is acceptable as a trade-off. I also prefer optics with a reputation for durability. So I end up with...

Aimpoint CompM4s for close.
ACOG TA11 plus RMR for general purpose.
Nightforce NXS 2.5-10 plus RMR for SPR-ish type rifle.

 

[nwriplip]

I just bought a Burris AR332 3x prism sight that I'm absolutely in love with. Highly effective out to 150.

 

[Member 53328]

Aimpoint micro. Period.

 

[Trunkmonkey]

Quality lvpo's are too heavy for my tastes besides a few, because I run everything with a suppressor and that adds a ton of weight. I run an Aimpoint micro with a magnifier, and remove the magnifier if I'm not shooting distance on my 11.85". You kind of get the best of both worlds there but eye relief is short and limited field of view with the magnifier, and unlimited field of view and no eye relief without it. On my 16" I really love a 4x acog with offset dot. The ta-31 acog can be 13oz with a different mount. That is what an Eotech weighs. Another 2.5 oz for an offset dot and mount. The short eye relief doesn't bother me, and the field of view is so nice it makes it feel like 5x magnification. Prism optics are so simple they are extremely rugged, and no batteries are used for the acog. On my 11.5" I like to run a 1.5 5oz TA44 acss acog. It's basically an Aimpoint size prism optic with a drop reticle and Eotech like outer ring. I also have another 16" with an expensive 1-8 lvpo that just sits in the safe as my particular scope is just to heavy. I should sell the optic, but it's great for making tiny groups.

 

[ar addict]

Trijicon MRO green dot is my choice for old eyes.
Whatever you choose don't let price be most important.
buy once, cry once.

 

[MasterChief]

Trijicon acog for me, but again Trijicon, your preference.....2nd would be Aimpoint

 

[titsonritz]

Quality lvpo's are too heavy for my tastes besides a few, because I run everything with a suppressor and that adds a ton of weight. I run an Aimpoint micro with a magnifier, and remove the magnifier if I'm not shooting distance on my 11.85". You kind of get the best of both worlds there but eye relief is short and limited field of view with the magnifier, and unlimited field of view and no eye relief without it. On my 16" I really love a 4x acog with offset dot. The ta-31 acog can be 13oz with a different mount. That is what an Eotech weighs. Another 2.5 oz for an offset dot and mount. The short eye relief doesn't bother me, and the field of view is so nice it makes it feel like 5x magnification. Prism optics are so simple they are extremely rugged, and no batteries are used for the acog. On my 11.5" I like to run a 1.5 5oz TA44 acss acog. It's basically an Aimpoint size prism optic with a drop reticle and Eotech like outer ring. I also have another 16" with an expensive 1-8 lvpo that just sits in the safe as my particular scope is just to heavy. I should sell the optic, but it's great for making tiny groups.

I agree, a heavy scope completely changes the balance of an AR. The Kahles 1-6x24i is 16.9 oz I put it top of a 1.93" Scalarworks LEAP Mount and it is very managable. Weight was one of the main reasons I got it and goes on my general purpose do all gun.

My dedicated home defense gun wears an Aimpoint Micro also on a Scalarworks Mount.



*****on the Kahles*****

Josh Costa, Costa Defense: The Kahles 1-6 has been around for a long time, and in my opinion, it is the very best 1-6x low power variable optic on the market, hands down. It is in second focal plane, which is good and bad, but I highly recommend the optic for anyone who likes to run shooting courses, shooting zero to 300 fast and on the move, or for 3-Gun guys. The reticle does not offer a ton of help as far as windage, follow-up shots, or hold overs…but with an AR where it's point of aim, point of impact on steel is out to 300 meters, it doesn't really matter.

Kahles 1-6 SM1
The 1x is where the Kahles 1-6 really shines…It's absolutely insane. In my opinion, it's better than running any dot on the market. It has the widest field of view, and the clarity and brightness is also incredible. The SM1 reticle looks a lot like an Eotech…It's quick to pick up and do CQB training with it. With that reticle, it's like a dream. It's insanely fast.

The optic is also very light. It's about a half ounce heavier than the NX8, but it is substantially longer. Finally, the price point is right at about $1,999. A lot of guys can get into that, and when they do, they are looking at an uber-premium experience.

https://www.arbuildjunkie.com/best-low-power-variable-optic-lpvo-expert-advice/

A good discussion on weight and balance early in the vid (3:00min mark)...

 

[titsonritz]

Or maybe a backup rear and fixed front post? Lower 1/3rd co-witness vs. absolute?

I have two carbines with Aimpoint Micros, both have fixed BUIS, one has a FSB with an LMT L8A rear sight, the other has Scalarworks PEAK front and rear sights. Both Micros are on 1/3 co-witness Scalarworks mounts.

 

[titsonritz]

Trijicon MRO green dot is my choice for old eyes.
Whatever you choose don't let price be most important.
buy once, cry once.

I considered moving to a green dot but decided to stick with red to contrast with my green laser.

 

[Trunkmonkey]

I agree, a heavy scope completely changes the balance of an AR. The Kahles 1-6x24i is 16.9 oz I put it top of a 1.93" Scalarworks LEAP Mount and it is very managable. Weight was one of the main reasons I got it and goes on my general purpose do all gun.

My dedicated home defense gun wears an Aimpoint Micro also on a Scalarworks Mount.

Those Scala works mounts are expensive but really a needed mount. So light, with so many features. I think Leupold, Kahles, Nightfroce, and some others are definitely decently light. They all cost of course. No arguing that the versatility of an lvpo is really useful if weight and uses are needed. There really isn't one gun or accessory to rule them all, just ones that do everything good, or do some things the best.