Sighting in acog

[Scottn]

I have a ta 31 acog with the red chevron, my ar has a 14.5" barrel. I sighted in at 100 yards, but was reading that the Bdc lines are based on a 20" barrel, and I should sight in at 50 yards or 1.5" high at 100 yards (for m193). Anybody have any expertise at this? I mostly use m193. The acog case says 223 Bdc/ft red chevron bac if that matters.

[Kwikvette]

I've sighted in at 100 yards and never had an issue; this is with my 10.5" pistol all the way up to my 16" rifles.

The acog is a combat optic and is not meant to be a precision scope. The built-in BDC is plenty accurate if you're aiming at man-sized targets.

[Droppin Deuces]

Not all ACOG reticles are created equal. Mine, for example is specified as M4/M249 and 62gr M855. Also, I believe the subtensions represent meters, not yards. Which means while you're probably fine for plinking and whatnot if you zero at 100 yards, but your ranging capability is reduced the farther you extend.

[Rusty_Shackleferd]

I have a ta 31 acog with the red chevron, my ar has a 14.5" barrel. I sighted in at 100 yards, but was reading that the Bdc lines are based on a 20" barrel, and I should sight in at 50 yards or 1.5" high at 100 yards (for m193). Anybody have any expertise at this? I mostly use m193. The acog case says 223 Bdc/ft red chevron bac if that matters.

From what I've read on similar posts to yours (Google your question, lots of info to be found on this subject) the manual instructs you to sight in at 55 yards to achieve a 200 yard zero, which also "calibrates" your BDC. I don't own an ACOG, so take my work with a grain of salt.

[Sniper3142]

A quick and easy search on YouTube resulted in a number of results. Google would be just as easy.

https://www.youtube.com/watch?v=jsKq2I_iJ-0

https://www.youtube.com/watch?v=eR6pBRtfmQI

https://www.youtube.com/watch?v=feNGU49XrAY

https://www.youtube.com/watch?v=Z4GvdHh5xcM

[Scottn]

Lots of stuff for the ta31rco, not much about how to sight in for 14.5 with a regular acog. I'm gonna keep the 100yard sight in, it's good enough

[teflondog]

I have a TA31 ECOS and it's mounted on a 14.5" barrel with 1:7 twist. I have mine zeroed at 100 yards and the BDC is close enough out to 400 yards. I'm thinking of switching to a 50 yard zero so I don't have to worry about using the BDC since most of my shooting is within 250 yards.

[AdorMe]

There are two types of ta31 rco's, one for the m4 and one for the m16a4. Since you said yours was for a 20 inch barrel im going to assume its for the m16a4. The ta31 rco is used for a 55 grain bullets. Yes its specifes (55gr) that in the trijicon website for the ta31 a4 reticle. But i was actualiy in the Marine Corps and we used the 62 gr greentips. Since the acog is for meters not yards 100 yards would equate to 91.44 meters. I have one for the m4 and just sighted it in for100 yards meaning top of the red chevron on my 16in ar. Which is fine. Also there is an article or other forum where marines on
The
Range switch acogs on the rifles and did a before and after shoot and the difference was almost negligible. I dont feel like finding the article though.

Lomg story short, I dont think it really matters if you sighted it in for 100yds. I was on the range in okinawa during a pre-typhoon weather and let me tell you that using that reticle in that of wind and shooting on the 500 yard line was like pissing in the wind. I was basically aiming at my neighbors target to my left just to hit mine haha