The Primary use of my 16" Carbine is going to be for Home Defense and possibly 3 gun .  For a budget of  about $1200 which would you chose?  The M3 and the 3Xmag or a an ACOG?  I like the idea of the flexibility that the Aimpoint set up offers and am leaning that way, however I am curious as to the thoughts of shooting with the ACOG ocluded at short distances.

Did you ever consider a variable 1X4 scope.  I have owned the Aimpoint/magnifier combo and it was not at all what I thought it would be.  There is no bullet drop like the ACOG and no BDC Turrets.  I switched to the IOR 2X12-32 and I wouldn't want any other scope.  There are several low power variable scopes out there like the Leupold CQT, Leupold 1.5X5. IOR 1.1X4, Horus Vision, and the ultimate scope, the Schmidt and Bender Short Dot.

Aimpoints:
A:  Uses:  (0-100 Yards)
1.  One of the best CQB (Close Quarters) sight available due to rapid target acquisition.
2.  Good all purpose Military/Law Enforcement sight.  Limited only by 1X magnification.
3.  Excellent for hunting where speed is desired over magnification.

B:  Pro’s:
1.  Generally very rugged.
2.  Unlimited eye relief.
3.  Parallax free (Dot does not need to be centered in the scope.).

C:  Con’s:
1.  Uses batteries.  (Although some have a battery life of 50,000 hrs.).
2.  Can fail.

ACOG's
A:  Uses:  (50-300 Yards)
1.  Good CQB scope with enough practice.  Best when used in open areas where magnification can be used.
2.  Best all purpose Military scope.
3.  Excellent for hunting where speed and magnification is desired.

B:  Pro’s:
1.  Generally very rugged.
2.  No batteries.
3.  Fixed magnification for simplicity.
4.  Parallax free (Dot does not need to be centered in the scope.).

C:  Con’s:
1.  B.A.C. requires practice.
2.  Can fail.
3.  Expensive.
4.  Short eye relief.

Low-Power Variable Scopes:
A:  Uses:  (0-300 Yards)
1.  Good CQB scope.
2.  Good all purpose Military/Law Enforcement scope.
3.  Good for hunting where speed and magnification is desired.

B:  Pro’s:
1.  Variable magnification offers options.  (1-4X magnification.).
2.  Generally very rugged.
3.  Optical glass makes identification easier.
4.  Batteries not an issue since reticle is black.

C:  Con’s:
1.  Not parallax free (Dot needs to be centered in the scope.).
2.  Eye relief is critical.
3.  Can be very expensive.

paulosantos thanks for the great reply.  I had not given a variable scope much of a thought as I have been hung up on having a red dot.  I read your review of the IORand will now have to contemplate other options....

i too would look into a variable powered scope in that range.

You're welcome.  Remember, pick something that you want for your needs.  The red dots and the ACOG's are great scopes, but they more geared for Military/LE because they were designed for quick target acquisition and speed.  The variable scopes are designed more for precision.  They are also fast, but more for accuracy.  Good luck.

Quoted: The Primary use of my 16" Carbine is going to be for Home Defense and possibly 3 gun .  For a budget of  about $1200 which would you chose?  The M3 and the 3Xmag or a an ACOG?  I like the idea of the flexibility that the Aimpoint set up offers and am leaning that way, however I am curious as to the thoughts of shooting with the ACOG ocluded at short distances.

If this is a combat weapon please only consider military grade optics that can stand up to abuse.  

If you have the money (2000$) look at the S&B short dot it is a great combat grade 1-4 power scope it has a huge fan base and is in use by Spec ops.  

Here are my optics choices and why I picked them.  
M4 14.5  Aimpoint plus magnifier

A4  20.0  Ta31F ACOG

First the M4. I chose the Aimpoint combo because I wanted a weapon that was fast close up and would allow me to identifiy targets at distance.  The Aimpoint combo is much faster at BAC than the ACOG. Plus you can adjust the brightness level on the Aimpoint combo thats somthing the ACOG is uncapable of.   Because you can adjust the brightness you will be able to use a magnified two eyes open method of shooting that the ACOG is not as good as at because of the lower brightness level.  Also the if you have to you can remove the magnification to use the weapon in vehical ops where a 1x sight will dominate.  The Aimpoint magnification is excellent for quickly identifing targets and engaging them.  The cons to the aimpoint magnifier is that it has no BDC to help you determine drop at distances past 300meters. Basically I chose this combo because it is tough has the best battery life is usefull for CQB and is also usefull at distance.  One of the biggest pluses to this system is the battery life 50000 hrs thats like 5 years.  

I chose the ACOG because it is more usefull at distance and has a BDC.  I put this optic on a 20 A4 because the ACOG is a better optic for 100 meter to 600 meter shots. The ACOG is usefull at CQB but is not as good as the Aimpoint combo.  

I broke it down like this

Aimpoint+magnifier
Great at CQB
Ok for distance shots (0-300 meters)  
perfect for 14.5 in barrel

ACOG
Ok for CQB
Great for distance shooting (100-600 meters)
perfect for 20.0 barrel

so you dont think I am talking out of my ass here are my weapons

Quoted: Quoted: The Primary use of my 16" Carbine is going to be for Home Defense and possibly 3 gun .  For a budget of  about $1200 which would you chose?  The M3 and the 3Xmag or a an ACOG?  I like the idea of the flexibility that the Aimpoint set up offers and am leaning that way, however I am curious as to the thoughts of shooting with the ACOG ocluded at short distances. If this is a combat weapon please only consider military grade optics that can stand up to abuse.

A home defense weapon isn't the same as a "combat" weapon.  Sure, it needs to be rugged, but features like "surviving a fall from a helicopter", "submersible to 66ft", "night vision compatible"...  those just aren't going to make any appreciable difference to an AR leaning against the nightstand.  While your suggestions are certainly great optics,  just because they aren't used in "combat" doesn't make some of the other quality optics available unsuitable or fragile.

Everyone who's ever owned an IOR always starts off with "built like a tank".  IOR scopes have been used in combat, and were designed for military use.  They are also a lot cheaper than the short dot.

The Trijicon AccuPoint TR21r (one of my favorites) gives you CQB and longer distance work, doesn't EVER need batteries, and is also "has a huge fan base and is in use by Spec ops.".  It's also a big favorite for many 3-gun competitors.

Here's my humble and practical suggestion on optics with your budget...

First, get an Aimpoint.  Go ahead and get it now since you know you like it and we all know it's functional.  You said "for HD and maybe 3-gun" which says to me "HD NOW, 3-gun later".  

For HD use, you won't need ANY magnification.  You don't want any distored image, no nothing to distract you from keeping both eyes open and focusing on the target.  In other words, Aimpoint .  Get a LaRue mount for the Aimpoint so you'll have QD capability with return to zero.  

Next, spend more time researching your magnified options.  Shoot with your Aimpoint and get proficient with it.  (and with your iron sights).  You might even want to save another $100 or 2 while you're waiting.  After you've read about, looked through, ask questions on all the magnified optics you like, THEN you can purchase the magnified optic.

If you get the IOR, that's $650 plus mount, so it's not far off your budget.

The Trijicon TR21r is around $550 plus mount, so again, reasonable for your price range.

If you still find you want the Aimpoint magnifier, you've already got the Aimpoint.

Another great thing about the Aimpoint is, if you decide you the other options better, the Aimpoint holds it's value very well on the EE.

Jus my humble, non Spec Ops opinion of some very good quality optics choices for your stated uses.

Quoted: Quoted: Quoted: The Primary use of my 16" Carbine is going to be for Home Defense and possibly 3 gun .  For a budget of  about $1200 which would you chose?  The M3 and the 3Xmag or a an ACOG?  I like the idea of the flexibility that the Aimpoint set up offers and am leaning that way, however I am curious as to the thoughts of shooting with the ACOG ocluded at short distances. If this is a combat weapon please only consider military grade optics that can stand up to abuse.   A home defense weapon isn't the same as a "combat" weapon.  Sure, it needs to be rugged, but features like "surviving a fall from a helicopter", "submersible to 66ft", "night vision compatible"...  those just aren't going to make any appreciable difference to an AR leaning against the nightstand.  While your suggestions are certainly great optics,  just because they aren't used in "combat" doesn't make some of the other quality optics available unsuitable or fragile. Everyone who's ever owned an IOR always starts off with "built like a tank".  IOR scopes have been used in combat, and were designed for military use.  They are also a lot cheaper than the short dot. The Trijicon AccuPoint TR21r (one of my favorites) gives you CQB and longer distance work, doesn't EVER need batteries, and is also "has a huge fan base and is in use by Spec ops.".  It's also a big favorite for many 3-gun competitors. Here's my humble and practical suggestion on optics with your budget... First, get an Aimpoint.  Go ahead and get it now since you know you like it and we all know it's functional.  You said "for HD and maybe 3-gun" which says to me "HD NOW, 3-gun later".   For HD use, you won't need ANY magnification.  You don't want any distored image, no nothing to distract you from keeping both eyes open and focusing on the target.  In other words, Aimpoint .  Get a LaRue mount for the Aimpoint so you'll have QD capability with return to zero.   Next, spend more time researching your magnified options.  Shoot with your Aimpoint and get proficient with it.  (and with your iron sights).  You might even want to save another $100 or 2 while you're waiting.  After you've read about, looked through, ask questions on all the magnified optics you like, THEN you can purchase the magnified optic. If you get the IOR, that's $650 plus mount, so it's not far off your budget. The Trijicon TR21r is around $550 plus mount, so again, reasonable for your price range. If you still find you want the Aimpoint magnifier, you've already got the Aimpoint. Another great thing about the Aimpoint is, if you decide you the other options better, the Aimpoint holds it's value very well on the EE. Jus my humble, non Spec Ops opinion of some very good quality optics choices for your stated uses.

I was only refering to scopes that are not of high quality.  All of the scopes you listed are military grade.  I find that on three gun matches trying to change magnification on any of the variable power scope is time consuming and can create unwanted situations.

The Trijican TR21 is a good variable power scope and I was not knocking it in any way.  I have found that fliping or turning rings to change magnification is a little to complex when you are under a clock.  I made my choices and I am happy with them.  But if you intend to bug out or are expecting combat conditions to ever happen to you try to get a military grade scope.  And yes the IORs are combat grade scopes no doubt they are built like tanks I have one mounted to a SLR95 Ak clone.  

If you are really stuck and can't decide, you can always get the ACOG TA31DOC.  I forgot to mention that option.

Ar15-sweety - thanks for the valuable input, it is nice to hear from a member that has both setups that I have been contemplating.  Thanks for the pics - very nice weapons!  Onslaught called it dead on - HD now and 3-gun later.  I am a civilian, so odds are my carbine will not get dropped out of a helicopter but I do want to buy top quality products that are available to me.  I have another week or so before I will need to make a purchase, I appreciate all of the input.