Quick question about RDS/1-4s/ACOGs

[rojocorsa]

So last time I did a search (I always do), and I didn't find the specific answer I was looking for.

So I understand that RDSs and Holosights are primarily for CQB type fast shooting up close. Out to what distance are these things effective? Can you use them to make hits at 500m or something like that? (I ask since one can with iron sights).


But I am curious, what is better for a general purpose carbine/rifle? An RDS or some kind of low power scope?


Also, just how fast are these 1-4x scopes? (I know ACOGs are like the same thing but more expensive, so I don't have any particular questions about them).

I am just not sure, and I also have no real experience with either.

Thanks guys.

[Badger89]

Under what circumstances? What size target? Big factors, IMO.

I had a Nikon 2.5-10x scope on my last AR, the one I am replacing it with will most likely wear an EOtech and a 4x magnifier. The scope was excellent past 100 yards, but it had two shortcomings. First was the minimum magnification. 2.5x doesn't sound like much, but try to hit a moving target, or a stationary target while you are moving and 25 yards or less. Doable, yes, but I wouldn't say it's easy. I'll lump ACOGS in this category as well. My friend just got back from Afghanistan - he runs an ACOG on his M4 for the longer distance engagement you can get into over there. He reiterated my feelings about magnified optics saying the ACOG was great for human sized targets at 100 yards or more, but closer than that he just indexes his body and puts rounds down range for the most part.

The second shortcoming of my scope applies to 1-4x scopes as well - limited eye relief. Even at 1x, you still need to keep your eye in that ~2-3 inch window to see through the scope. If you can keep a good cheek weld everything's fine and dandy, but if you have to break that for any reason, well again you're going to be doing the point and shoot thing.

Dot sights are not without shortcomings either though, the biggest one being the lack of magnification. How good are your eyes? If you're like me, seeing a target at 500 yards clearly enough to identify is a little difficult. You can add a magnifier on a flip-to-side mount behind one to solve that problem, if you have the cash, rail space and want to add the weight. Another big disadvantage for dot sights is the actual size of the dot. Many are geared more for CQC and have larger dots, 2MOA, 4MOA, or even bigger. That means regardless of if you have a magnifier or not, at 500 yards your dot is going to be covering up 10" of your target (2MOA), 20" of your target (4MOA) or more. So like I said, how big is your target? Hard to aim at something to small to see behind your dot. This is why I'm strongly leaning toward the EOTech. The 1MOA center dot will only cover ~4.4" at 400 meters (the max I plan to shoot with this rifle) and the 65MOA outer ring makes an excellent ranging tool. It's hard to hit anything that far away if you can't calculate your drop and drift.

Just my $.02.

[rojocorsa]

Under what circumstances? What size target? Big factors, IMO.

I had a Nikon 2.5-10x scope on my last AR, the one I am replacing it with will most likely wear an EOtech and a 4x magnifier. The scope was excellent past 100 yards, but it had two shortcomings. First was the minimum magnification. 2.5x doesn't sound like much, but try to hit a moving target, or a stationary target while you are moving and 25 yards or less. Doable, yes, but I wouldn't say it's easy. I'll lump ACOGS in this category as well. My friend just got back from Afghanistan - he runs an ACOG on his M4 for the longer distance engagement you can get into over there. He reiterated my feelings about magnified optics saying the ACOG was great for human sized targets at 100 yards or more, but closer than that he just indexes his body and puts rounds down range for the most part.

The second shortcoming of my scope applies to 1-4x scopes as well - limited eye relief. Even at 1x, you still need to keep your eye in that ~2-3 inch window to see through the scope. If you can keep a good cheek weld everything's fine and dandy, but if you have to break that for any reason, well again you're going to be doing the point and shoot thing.

Dot sights are not without shortcomings either though, the biggest one being the lack of magnification. How good are your eyes? If you're like me, seeing a target at 500 yards clearly enough to identify is a little difficult. You can add a magnifier on a flip-to-side mount behind one to solve that problem, if you have the cash, rail space and want to add the weight. Another big disadvantage for dot sights is the actual size of the dot. Many are geared more for CQC and have larger dots, 2MOA, 4MOA, or even bigger. That means regardless of if you have a magnifier or not, at 500 yards your dot is going to be covering up 10" of your target (2MOA), 20" of your target (4MOA) or more. So like I said, how big is your target? Hard to aim at something to small to see behind your dot. This is why I'm strongly leaning toward the EOTech. The 1MOA center dot will only cover ~4.4" at 400 meters (the max I plan to shoot with this rifle) and the 65MOA outer ring makes an excellent ranging tool. It's hard to hit anything that far away if you can't calculate your drop and drift.

Just my $.02.

Thanks for your response. I guess the size of the target would be man-sized. This site is about fighting rifles, after all.

[Badger89]

Man sized gets pretty small at 500 yards. That's why I'm leaning toward the EOtech. Cut out a 5" circle, tape it to your chest and stand in front of the mirror. That's what you'll see with an Eotech at 500 yards. I'd like the longer battery life and arguably stronger construction the Aimpoints offer, but I can't bring myself to accept a 2MOA dot for that kind of distance. My max range will be 400 meters, which is 440 yards, give or take. The reason I measure in meters is because the 65MOA ring will measure 70.85" at 100meters, or approximately 5'11". The average height of men over 20 in the U.S. is approximately 5'10", so at 100 meters a man will fill the ring, at 200 half the ring, at 300 1/3 of the ring and at 400 1/4 of the ring. Like I said before, range estimation is key for longer shots.

[Apricotshot]

For MOST people who live in a urban or suburban area a RDS makes the most sense. RDS are good out to wherever you can see and account for bullet drop. So it will be different based on the shooter's skill level, eyesight and knowledge of his or her rifle's dope. A 2MOA Aimpoint is hard to beat for this application IMO.

[Failure2Stop]

While I can get hits out to 500/600 meters with a dot, they are far more applicable from 3 to 200 meters.
Big issues for stuff past 200: no hold point references for long range drop/wind compensation, no ability to rapidly spin turrets for a longer range zero, and no magnification for target detection or discrimination. Dot blur and bloom can obscure small targets at long range or make precise placement of the desired strike point difficult.
Basically, if you have to actually look for a target, the RDS won't be the best choice.

ACOGs are decent 50 to 500 meter day optics if you are shooting at torso sized targets with ammo that approximates the BDC, and have a very small footprint and weight for their performance level. Very robust. Shitty close-range and long-range performance, especially in transitional lighting conditions.

Low powered variables: I am just as "fast" with them as I am with an Aimpoint/EoTech/or irons at close to mid-range, and they give better long-range performance than anything else, if properly selected.

[armakraut]

I own acogs and RDS's, but variable is the way to go now that 6 and 8 power rectors are available at decent prices. They work like an RDS up close, and you can identify things at longer distances.

Nikon 1-4X monarch African, can be had for less than $300, excellent scope for the money. Very visible reticle, it just plain works.

I think the 1-4X Trijicon TR24's are still about $700-800-ish, again, excellent scope for the coin, the red triangle reticle is the most aimpoint-like. Fiber optics will always be on, in that respect no other scope can match its capability. Unfortunately other variables that get to 6 and 8x on the high end pretty much outclass it in longer range identification and shooting. Trijicon reps have been talking about an 8x scope for a while, but nothing has hit the market yet.

The real budget minded sleeper is the 1-6X Leupold VX-6 scope with aimpoint bright illumination, less than $850 shipped some places, their german #4 without illumination is less than $750, they also have a 2-12x scope (!) That's less money than most competing high end 1-4x scopes AND it's a better scope than most in terms of illumination, clarity and weight.

Vortex has an excellent 1-6x HD II scope for $1,200-ish with BDC and aimpoint bright illumination. Heavy, but has a great eye box and superb clarity. Leupold's MK6 34mm scope goes for a few hundred more also.

For $1,900 you can get a 1-8x USO SR-8 scope. These spank most other scopes, even the krauts are jealous. It's almost like having a red dot and a traditional 9 or 10x marksman scope in one. Lighter than the Vortex too by a couple oz.

[8200rpm]

Optics I've used (recreationally): Aimpoint Micro, ACOG TA33, Vortex 6-24X out to 600 yards, and Vortex 1-4x (no field use).

Red dots are virtually idiot proof out to 250 yards. Place dot over target, press trigger. If you can see a 18"x24" object within 250, you'll hit it. FOV is unencumbered and there is virtually no optical distortion, parallax, or eye relief limitations.

ACOG's with BDC's are awesome for 50-500 yards. The TA33 models are really compact and light. Magnification helps you see targets out further. Within 50 yards, the magnification, FOV, and looking through a straw effect might be distracting. I suppose familiarization through training and use can overcome this effect.

1-4X scopes are like an ACOG if you leave it at 4X. I'm really not convinced of the merits of a variable power optic at 1X. It is an improvement over using a fixed 3X or 4X close in, but at 1X, it is NOT optically the same as an unmagnified RDS. Essentially, it's like having one eyeball 16" in front of your face. Again, it's probably something that one can overcome with training and practice.

I'm not sure how you define "general purpose", but for a defensive carbine in urban settings, RDS seems sufficient. If "general purpose" encompasses rural/wilderness settings with the high possibility of threats at 250 yards or more, the ACOG or 1-4,6,8X probably would be the better option.

Ultimately, you'll need to define the scope (no pun intended) of your "general purpose" carbine and honestly assess the probability of encountering threats at given distances.

[ra2bach]

Optics I've used (recreationally): Aimpoint Micro, ACOG TA33, Vortex 6-24X out to 600 yards, and Vortex 1-4x (no field use).

Red dots are virtually idiot proof out to 250 yards. Place dot over target, press trigger. If you can see a 18"x24" object within 250, you'll hit it. FOV is unencumbered and there is virtually no optical distortion, parallax, or eye relief limitations.

ACOG's with BDC's are awesome for 50-500 yards. The TA33 models are really compact and light. Magnification helps you see targets out further. Within 50 yards, the magnification, FOV, and looking through a straw effect might be distracting. I suppose familiarization through training and use can overcome this effect.

1-4X scopes are like an ACOG if you leave it at 4X. I'm really not convinced of the merits of a variable power optic at 1X. It is an improvement over using a fixed 3X or 4X close in, but at 1X, it is NOT optically the same as an unmagnified RDS. Essentially, it's like having one eyeball 16" in front of your face. Again, it's probably something that one can overcome with training and practice.

I'm not sure how you define "general purpose", but for a defensive carbine in urban settings, RDS seems sufficient. If "general purpose" encompasses rural/wilderness settings with the high possibility of threats at 250 yards or more, the ACOG or 1-4,6,8X probably would be the better option.

Ultimately, you'll need to define the scope (no pun intended) of your "general purpose" carbine and honestly assess the probability of encountering threats at given distances.

I'll give you one advantage of a 1-4 @ 1x over a RDS - if you have astigmatism a RDS can give a fuzzy imprecise aiming point. a magnified optic will clear that up...

[rojocorsa]

I happened to go shooting this weekend, and I ran into a gentleman who had an ACOG TA01NSN. I asked him if it was OK to check out and look at some targets in the distance. He was even nice enough to let me have a few shots with it.

I really liked it, especially because it had the BDC and the eye relief didn't seem wonky like it can with traditional scopes.

Since I am more interested in shooting targets at this time (I can't really do run and gun shit; much less when I can't even drop mags in CA), I think I will just look around for an ACOG like this. It should fit my range needs nicely. I'm sure that if I even get to go to a carbine class or something, that I can find/borrow an aimpoint.

I think (but I'm not 100% sure about it) that I may have an astigmatism with my shooting eye anyway, and this isn't an issue with the ACOG).