Looking for feedback on the Trijicon TA31D-100581 4x32 BAC USMC RCO Riflescope - M855 / A4 / M4 and the TA31RCO-A4CP designed for the USMC's M16A4 weapon system (20” barrel). One is a chevron and one is a horseshoe. One is M855 bullets and the other one? Link here https://www.trijicon.com/products/details/ta31-d-100581 and https://www.trijicon.com/products/details/ta31rco-a4cp. This will be for a Colt AR15A4. Thanks
Rifle Scopes Trijicon ACOG
- Thread starter Count VonFuhrman
- Start date
I can give you a partial answer as I have the TA31D. Make sure your eyes are either young or your vision is excellent. I just had a total rebuild done to both eyes with in the past three weeks. I am now 20-20 in both eyes. Before surgery, is there anything other than a red dot there? After, life is good, everything was sharp.
When searching this optic I only ran across one comment that stated not everyone has 18 year old eyes.
Hope this gives you some insight.
Maxwell
When searching this optic I only ran across one comment that stated not everyone has 18 year old eyes.
Hope this gives you some insight.
Maxwell
Thanks for the reply. Eyes are good. Which one do you have?
I have the TA31-RCO M4 with the Chevron. If you're using a 20" you want the A4 version. Its calibrated for the 62gr SS109 projectile (g1 bc of .307) traveling at about 3100mv . The M4 reticle is calibrated for the SS109 at about 2950mv.
The glass is absolutely badass and clear.
I have my loads moving at about 2920-ish and it matches the BDC holdovers out to 500 all day long with full size IPSC steel.
You'll fucking love it.
The glass is absolutely badass and clear.
I have my loads moving at about 2920-ish and it matches the BDC holdovers out to 500 all day long with full size IPSC steel.
You'll fucking love it.
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Thanks for the reply. The Trijicon 100581 with horseshoe says for M4/A4 M855. Confused when they say for M4-14.5 inch barrel and A4 20 inch barrel. That close or is there a difference in barrel length. While the A4cp chevron calibrated for 20 inch barrel only?
I have a TA-33, 3X.
I went that route due to reports of how awful the eye relief is on the 4X Acogs.
I really like the TA33 on my carbine switching from a 1-8X USO. It really skinnied it up.
The sucky part about the TA-33 and as @Maxwell alludes to "vision matters"
No ocular diopter adjustment on any Acog.
I usually shoot sans perscription glasses setting up my scopes to my vision deficiencies.
No good with the Acog - I have to use my glasses to see the reticle and even than its a small reticle.
Still though I find it functional and look forward to trying that set up out on a mid range carbine class.
I have another AR with an Aimpoint Pro red dot. Close in it does everything my ACOG does and I dont need to use glasses to cover appropriate sized targets with the dot. Its really handy out to 200 yards and does well on having steel make noise out to 300 - the furthest distance I have had to play with it.
I dont not recommend an Acog but really try to fondle before handing over cash.
I went that route due to reports of how awful the eye relief is on the 4X Acogs.
I really like the TA33 on my carbine switching from a 1-8X USO. It really skinnied it up.
The sucky part about the TA-33 and as @Maxwell alludes to "vision matters"
No ocular diopter adjustment on any Acog.
I usually shoot sans perscription glasses setting up my scopes to my vision deficiencies.
No good with the Acog - I have to use my glasses to see the reticle and even than its a small reticle.
Still though I find it functional and look forward to trying that set up out on a mid range carbine class.
I have another AR with an Aimpoint Pro red dot. Close in it does everything my ACOG does and I dont need to use glasses to cover appropriate sized targets with the dot. Its really handy out to 200 yards and does well on having steel make noise out to 300 - the furthest distance I have had to play with it.
I dont not recommend an Acog but really try to fondle before handing over cash.
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Thanks for that reply and consideration.
I went with the M4CP model because that reticle is for the 14.5" barrel. The A4CP is for the 20" barrel. The shorter the barrel, the less velocity you'll get with the same ammo. I dont have specific experience with the horseshoe reticle.
I was seriously considering the TA-33 for myself for a while. The 4x models pretty much require you to run them nose to charging handle due to the short eye relief. I ultimately ended up going with a Trijicon TR-24 1-4x scope with the red triangle reticle. Like the ACOGs, it doesn't need any batteries because it also illuminates the reticle with fiber optic. It also has a diopter adjustment for those of us with older eyes. Its easier for me to run it both eyes open like a red dot because I can dial it down to 1x and the field of view is much wider than any red dot. The eye relief is rather forgiving compared to a 4x ACOG. When distance is required, I just dial it up to 4x. The only downside is that there is no BDC reticle. I just zeroed it for a 50/200 yard zero. For 300 yards on an IPSC target, just hold on the head and your hits will be in the chest area. Ultimately, it will depend on the main purpose you want the rifle to serve.
That looks like a great option.
I just had a hair across my ass to slim down my 16 inch AR. The USO 1-8X is great but kind of big.
At the time I was thinking this I also was thinking the S&B 5-25 PMII on my 308 LMT was kind of dumb.
The S&B is now in fleet reserve, the .308 has a 1-8X and the .223 is running the TA33.
I really like the ACOG I just dont like that in order to use it Im kind of dependent on my glasses.
Im really comfortable behind it as the eye relief is very much like a typical scope.
OP should consider what he has for other tools.
My rifle with the red dot Id consider 100 yards and in. The ACOG, confidence to 300 but could probably scare stuff up to 600.
Guns are like torque wrenches.
You cant just have one.
Too much wrench leaves you wanting on the little fasteners and too little is useless for the big stuff.
You could probably get away with owning three torque wrenches and three guns, the middle one being the one you probably use the most.
I hide a A4 with the rco one. I really liked it. But I never hardly shoot past 100 yards so I traded it for a comp4s aimpoint
Totally sound decision.
I dont understand why Trijicon didnt incorporate the ability.
Is it a cost issue, is it the bindon concept requires both eyes to be the same correction, is it they wanted to avoid possible "weakness" of another avenue for moisture to enter the optic body?
I could run it close in with the lit horseshoe like a red dot but any other utility of the reticle is lost without my glasses.
Not a big issue for me sitting at a bench but what about the private issued thick BCGs that just dived into a hole under fire and broke his lenses?
I have had two ACOGS over the years the TA31D-100581 4x32 BAC USMC RCO and another one that was calibrated for a 20" barrel I don't remember exactly which model, but I will echo what has already been said about the eye relief and needing great vision to see the reticle. I am just a civilian that used them to bang steel IPSC targets out to 800yds for fun and because they are built like tanks also for a unlikely SHTF situation. I finally got LPV scope a 1-8 to be exact and started using it for the same thing I was using the ACOG for. I found the ACOG was just sitting in the safe not being used so I sold it. For me a LPV 1-6 or 1-8 is so much better. ACOGs are great, but at the end of the day I had a really expensive fixed power scope with very poor eye relief and no diopter adjustment. BTW if you want a BDC reticle in a LPV scope the Primary Arms ACSS reticle is pretty good and I have found it pretty spot on out to 800yds. Before I get flamed and accused of being a mall ninja for suggesting a PA with the ACSS reticle I am not saying it's good for bench rest or F-Class competition that's not what it is designed for, but for banging full size 18"x 30" steel IPSC targets out to 800yds it works great. Funny how a ACOG with a BDC reticle is the best thing since slice bread, but any other scope with a BDC reticle is a total POS not worth using as a paper weight. (BTW Trijicon now has some ACOGs with PA's ACSS reticle.....LOL)
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I did a few articles comparing various 4 prismatic scopes. If you have young eyes or well corrected contacts (I am in the second category), they all work well. I looked at ACOG, HAMR, Spectre 4x, Hensoldt, Bravo4, etc. Personally, I prefer the Elcan Spectre 4x, but they all work. ACOG 4x32 was easily the most difficult for me to get behind, so if you are set on a Trijicon ACOG product, I would consider their 3x or 3.5x models.
If you are concerned with it not working well with your eyes, you will need a model with adjustable eyepiece. There, in terms of bang for the buck Crimson Trace 3.5x Battelsight is very attractive. I've been abusing one for a few months now and it works well. It kinda takes over the niche that Leupold's HAMR had before it was discontinued, but at half the price. Sig's Bravo4 also has an adjustable eyepiece. It is a bigger sight, but you get that crazy FOV with it in exchange.
ILya
If you are concerned with it not working well with your eyes, you will need a model with adjustable eyepiece. There, in terms of bang for the buck Crimson Trace 3.5x Battelsight is very attractive. I've been abusing one for a few months now and it works well. It kinda takes over the niche that Leupold's HAMR had before it was discontinued, but at half the price. Sig's Bravo4 also has an adjustable eyepiece. It is a bigger sight, but you get that crazy FOV with it in exchange.
ILya
Can't they make an ACOG with adjustable eyepiece?
Went with the TA-31D. No problem with eye relief. Thanks for replys
Im working on a load now to try and match up to the reticle in my TA-33 with the 69gr BDC reticle. Was pretty surprised Trijicon doesnt include the measurements in the manual. I contacted them directly to get which projectile, BC, fps and the drops in mils the reticle was marked for. Super responsive but they did check my serial number before providing the info. Was a bit surprised thats secret info lol. Good luck with the new glass- nice choice. Wish I had gone 31 over 33
Which Ta33 did you get?
TA33G-11. I actually really like the TA33 but I got a new rail on my AUG that has an ACOG mount built in very low. Low enough putting an RMR on top would be the tits to have a red dot and 4x without the weight of a LPVO. The field of view of the TA33 isnt even close to the 31 and my old eyes could use the 4x. If you are using the BAC though the 33 is faster. for me which is why I got it originally.
Thanks for the videos
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