Practical experience with ACOGs?

[Oleg Volk]

Grrr...I have one flattop (currently with EOTech 522) and one A2 rifle. I suppose I could get another flattop upper and go with the option sugegsted here (maybe make it a light 16"...would make sense but I keep coming back to 20" HBAR for some strange reason). Maybe if I manage to sell my Mak90 and Sig 232, I'll get another upper and a 4x ACOG (the mini-ACOGs don't have backup sights, right?)

 

[SodaPop]

Odd. Are there any "practical negative experiences" out there, or are some people just mad at what they can't buy?

Can't buy? Or can't justify the cost of?

I wonder what the military pays for them?

 

[Navy joe]

Soda, not flamin' just asking for negative user experience.

Oleg, with the carry handle mount you could knock the rear sight off and still be pretty close, not obstructed at all. I did fool myself once though, my killflash was shifted and cutting off a little of the top of the circle and I didn't notice, was shooting rather high as a result. I guess I'm just a anachronism, I can't stand flattops and feel that you have to do some contortionist act to align your eyes and face to a stock with no drop. The straight stock and pistol grip put my eye up where the iron sights are. For the ACOG I back my nose off the charging handle about an inch. Somtimes I like a little spot rubberized grip tape on the stock in the manner of a bow kisser button to get you used to sticking your face in the same spot each time.

Now that I asked for negative, I'll go for why positive for me. Someone alluded you could buy a real scope for the price of an ACOG. Yep, also could buy a wild night in Vegas or something, who cares. In their quest for "real" scopes many American gunners buy way too much scope. High magnification can help you shoot tiny groups but can really impact usability. It is "too much syndrome" I came into a Rem 700 that had a fixed 32x scope. I could shoot 5 shots touching all day long, I could also read what the NRA had to say on the bottom of the target at 100yds. My field of view at 200 was maybe 10 feet. I had enough trouble getting it lined up with my target, imagine something moving! If there are people shootnig 600 and more yds on iron sights you do not "need" high magnification. You also do not need the compromise variable power scope in most situations that an AR can handle. Variables have more moving parts.
Parts that like batteries, quit.

So, I like:
-Low moving parts count
-Lack o' batteries
-Low fixed magnification. Decreases extreme precision, increases shootability. (See also less moving parts)
-very durable construction
-compact size
-simple, repeatable mount. Rock solid.
-And finally, that cute little red crosshair I can see in the dead of night.

 

[Jeff White]

Ok, the model with the backup sights is the TAO-1 NSN. The BDC reticule is calibrated for M855 out of a 14.5", 1/7 twist barrel. The backup sights are pretty useless for anything beyond CQB range. The tritium illumination in the NSN model is amber in color.

The TAO-1 has a reticule BDC calibrated for M855 out of a 20", 1/7 twist barrel. the tritium illimination is red.

You may also run into some problems with the BDC mounting ithe NSN on the carry handle. It comes with the TA51 flattop adapter. The height above bore may be too much to make the BDC all that useful.

I'll try to take some pics of my set up.

Oleg,
Not that it's any of my business, but what do you want with a 20" HBAR? One of the advantages of the AR15 is it's light weight. I'd recommend a 20" govt. profile barrel, thin under the handguards and heavy forward of the front sight base.

Jeff

 

[Oleg Volk]

When I was shopping for rifle #1, I didn't know any better. When shopping for #2, I wanted a flat-top with integral front sight...couldn't find that in a light barrel. The only light barrels I've found have been A1 uppers or 16". Can my heavy 20" barrel be replaced with a light 20" without too much trouble? I do prefer rifles which aren't front-heavy.

PS: I am still not sure about "tactical" sling -- it helps to move and allows faster deployment, but makes off-hand much more wobbly compared with hasty sling...but regular sling sucks for cross-country walking. Ugh.

Is there a complete guide as to which ACOGs are set up for which barrel length (20") and bullet weight (55gr) and which reticle? The number of model designations is very confusing...

 

[Jeff White]

No problem changing the barrels. I'll even do it for you if you can't find someone local. Look in the equipment exchange at AR15.com, you should be able to find about any barrel you want. I'd recommend either a Colt or Bushmaster chrome lined barrel.

You might try Trijicon's website for descriptions of all their models. Have it bookmarked on the computer at work, I'll get the link tomorrow.

There are tradeoffs in everything. The best sling for shooting is not necessarily the best one for carrying. Trust me, you won't often shoot offhand anywhere but in bullseye competition. The exception will be CQB or the target that jumps up suddenly at close range. It should be part of your contact drill to seek a more stable shooting position. This will also lower your profile. Drop to prone or squatting as part of your contact drill for anything but a near ambush.

Here is a pic of my prototype Squad Designated Marksman's Rifle. It started as an Essential Arms pre-ban lower that had a Bushmaster 11.5" w/long flash hider A1 upper and two position collapsible stock. I sold off the upper and stock, added a Bushmaster V-Match flattop upper with A.R.M.S. SWAN Sleeve, Colt 1/7 20" govt. profile barrel, KAC M5 RAS, Armalite green furniture, Harris bipod, Eagle tac sling and magazine stock pouch, Trijicon TAO-1 4x32 ACOG on TA51 flattop base. While the thmbscrews on the Trijicon base aren't as fast as the hrowlevers on A.R.M.S. base would be, I can still get the scope off quickly and use the backup irons on the SWAN Sleeve should the scope fail.

Jeff

 

[Oleg Volk]

Looks like compact ACOGs have certain tradeoffs: 1.5x16 has longer eye relief and field of view than 1.5x24. Guess those two qualities beat brightness, esp. since exit pupil 10 2/3 is plenty anyay. Not even certain what eye relief means -- is it the distance at which the reticle is in focus OR mag distance fromwhich the whole field of view is visible or something else? Also - ACOGs are designed to be used with both eyes open...does this mean that some people can't use them at all? (I read something about that a while back)

Any down sides to compact models? I doubt that high magnification would necessary... Also, does any manufacturer make light barrel 20" uppers with flat top AND a fixed front sight?

 

[Zak Smith]

Eye relief for scopes is the distance between, roughly, your eye's lens, and the scope's lens to see the widest possible view through the scope.

Some, like Trijicon, will specify an optimal value.
Some, like Leupold, will specify a range.

For nose-to-charging handle on an AR-15, there will be about 1.5" distance from your eye to the rear end of the flat-top. Thus, to get correct eye relief on something with long E.R. (3.5" or so) like a Leupold with a nose-to-charging-handle stance, you'll need to mount the scope such that the rear lens of the scope is about 2" in front of the back of the flat-top, like this:
http://apollo.demigod.org/~zak/pictures/2003-03/b43.shtml

An ACOG with 1,5" eye relief should work properly with the rear lens at the rear end of the flat-top.

hope this helps

-z

 

[Onslaught]

What I haven't seen mentioned regarding the ACOG is the Bindon Aiming Concept. In short, it makes your optic a "non-magnified red-dot" when you're field of vision is moving, and a "4x optic" once you stop moving.

That, in my opinion, makes the ACOG more functional than either a red-dot or magnifying optic. The "donut of death" and Chevron reticle work better for this than the crosshairs, and although I can't afford one of my own, the ones I've tried out at the range have shown me that they are the BEST option for an AR. Also, given the BAC, I'd mount mine to the flat-top, with maybe a BUIS, just in case...

If you do a search at AR15.com, you'll also get a lot more positive feedback on the ACOG's and using the BAC.

Just my personal experience, I had a Reflex II for about 3 weeks... I didn't like it. I'm not knocking it, because lots of people do like them... but I didn't.

First, I didn't like the "yellow wash" effect of the oddly tinted lens, and I did have a hard time picking up the triangle at the covered range on even average-sunny days. It did absolutely nothing for me that a $175 red-dot sight couldn't do... except for the overall "triangle" concept. Someone should incorporate a triangle reticle into one of these multi-reticle red-dots. Great concept for an AR.

 

[Oleg Volk]

Hmmm...so switching of eye dominance I had with Aimpoint 2x red dot was normal? I like the looks of the triangle but that's not an option with AGOC scope, AFAIK...only chevron. At this point, I am considering crosshairs and chevron, not sure which would work best. My experience with scopes is limited to low-end 4s Simmons and 3x9 Bushnells, both unsatisfactory...

 

[Zak Smith]

Oleg,

The BAC ACOGs have the option of donut, chevron, or triangle reticle. In the 4x w/ BAC, the TA31 has the donut, TA31A has the triangle, TA31F has the chevron. The TA01* models are the 4x without BAC.

BTW: http://www.sableco.net/id10.htm

Sableco.net has a good summary of models and features, and they are great to do business with.

-z

 

[Bartholomew Roberts]

Oleg,

About 96% of the population can use the Bindon Aiming Concept according to Trijicon. Those who can't use it can still use ACOGs like a more traditional scope but won't enjoy any of the extra benefits from using them with both eyes open.

If you know you are going to use the ACOG on a carry handle and want the BDC feature, then I wouldn't get the TA01NSN, TA31F, or TA11F. Most of the time you can play with a ballistics calculator and get a decent match to the BDC just by changing the distance you sight in - but the 62gr flattop BDC used in those ACOGs will make it impossible to get a good match from a carry handle mount.

If you haven't seen this thread from arfcom yet, it is a good discussion of the ACOGs:

http://www.ar15.com/forums/topic.html?b=3&f=18&t=148926&w=searchPop

Compared to the EOtech or the Aimpoint, I can think of a few negatives for the ACOGs - one is that they aren't unlimited eye-relief and parallax-free like those two sights. The other is that you won't get dot-shift with either of those sights as eye dominance switches.

That's about it though... the ACOG has a lot of positives to it. It also is pretty versatile with the BAC option.

 

[Jeff White]

http://www.tacticalintervention.com/cqbsling.html

Check this link for a tactical sling that you can also use as a hasty sling. Don't know how well it works.

Jeff

 

[JShirley]

I've wanted an ACOG compact for years. My company (and Bat/Div/Corps) is using them for SDM rifles, which are currently M4's. (Everyone else in the company has M68 Aimpoints mounted.)

I plan on mounting TA50-2 to my FAL.

 

[Correia]

Jeff, thanks for that link. That looks like just what I have been looking for. I'm going to start a new post to get feedback on that sling.