Which ACOG for my M16A4 clone?

[Solidsnake87]

Hey guys,

I'm trying to decide on an ACOG model for my flat top M16A4 20" rifle build. Do they make one calibrated for flat top 20" rifles?

[Centurion_D]

Get the TA31F. That's the ACOG I have on my A4gery. You could go for the TA31RCO-A4 but you'll be spending more money.

[UBFRAGD]

Aren't they calibrated for caliber?

I got the TA33R-8 and it is suweeet!!

[chuck762]

On my A4 clone I have a TA11F because of the greater and more forgiving eye relief.

[reidnez]

Aren't they calibrated for caliber?

I got the TA33R-8 and it is suweeet!!

To my knowledge, yes, the milspec models are calibrated for 5.56 from a 20" barrel. They have a range-compensating reticle so they would have to be.

[technique]

I have always liked the TA31F..

[Solidsnake87]

Yeah, I know they are calibrated in .308 and 5.56--some depend on mount setup. The TA01 is specifically meant for 20" rifles that are using a carry handle to mount to. The specified flat top models seem to be for carbines. I'm just looking for something useable on a 20" flat top.

[chuck762]

They are all usable on flat top models but there will be a slight difference in the BDC. But the BDC isn't 100% accurate anyway with humidity, elevation, temperature, and ammo used.
Here is a chart showing the BDCs with different ammo and rifles.

http://www.ar15.com/forums/topic.html?b=3&f=18&t=229420

For hitting human sized targets which is what they are designed to do, they are all pretty close no matter what combo used. My TA 11F works fine on the 20 inch A4.

[Jicko]

Which ACOG for my M16A4 clone?

the obvious answer is "the ACOG clone"....







now for real.... TA11F....
(read the part about fixed power type 2 optics)

http://demigodllc.com/articles/fighting-carbine-optics-short-guide/?p=2

[Casual Observer]

TA31RCO-A4CP is a nice optic. I have the same one calibrated for a carbine barrel (the TA31RCO-M4CP) and it's great.