Opinions on AR-15s and the Colt 6920 with ACOG

[230therapy]

The whole point of this exercise is to acquire a rifle that can handle the Trijicon ACOG RCO 4 power optic (TA31RCO-M4CP). This is what makes the system deadly out to 600 yards (with 77 grain bullets). They don't make an optic for 7.62x39 (I'd stay with the AK-47 system if that were the case).

I am considering getting an AR-15. Price up to $1300-1600 is not an issue. The top of the list is the Colt 6920 because of the components, accuracy and reliability. I have received many recommendations for this rifle (including from guys in Afganistan who used theirs for 7 months in the field and some gun instructors). Recommendations for other rifles included a laundry list of required modifications. While not opposed to modifying the gun, I'd rather not if at all possible.

What other AR-15s perform at or above the Colt 6920's level with an ACOG? What modifications are required to attain this (if any)?

[Ash Hess]

Basically, Nothing. If you are planning to use bi pod and work long all the time I would add a free float to it.
If you are planning to be Uber-Door kicking-6 rounds in 1 second and then drop to prone, dynamicly of course ;), and shoot 2 MOA groups at 600 meters You have some work to do. But let the software guide the hardware.
My ISSUE M4 with non floated 7 inch KAC rail, laser, and Surefire light and ACOG RCO was dead nuts at 700.
remember ACOG BDC is set up for 62 grain green tip.

[230therapy]

Yeah, I'll have to map the deltas on between the BDC and the 77 grain bullets' performance.

I go to training frequently and this gun will be "proofed" during that training.

Any opinions on alternative brands and models?

[Ash Hess]

I am looking at the Daniel Defense M4. or a BCM mid length set up. Of course the Noveske's and such are nice. I watched the DD gun shoot a 3 MOA group today thru 4 different positions at 100 meters and my MP-15 and I pulled a 4 MOA group.
But I watched a custom built super AR shoot Patterns instead of groups. But the Colt will not disappoint.

[organdonor]

if i was going to build an spr right now i'd mate a lower with an 18" Larue Stealth upper.

[230therapy]

I looked at Daniel Defense...and the gun was $1500+. I'm not sure if I'm getting anything over the Colt 6920. The Knights Armament guns were $2,200+.

I'm tempted to get a refurbished Garand and call it good.

[Ash Hess]

that is a tempting thought. Going thru the CMP and even adding the Troy EBR Garand chassis, you are still below new AR price. hmm, maybe next gun.

I don't fault your logic. But there is always straying from the chart, building a "lesser" gun. I happen to know where there is a 2 MOA 20 inch barreled Olympic Arms flat top. I have watched this gun, with iron sights, hit 3 inch clays resting on the ground time after time after time.
Luckily, my 16 year old Daughter doesn't know she has a "lesser" gun. She only knows it cost 600 bucks a few years ago.

[Army Chief]

I had no idea that Sage even made a Garand EBR chassis until it was mentioned here. Interesting!

AC

[sundance435]

The whole point of this exercise is to acquire a rifle that can handle the Trijicon ACOG RCO 4 power optic (TA31RCO-M4CP). This is what makes the system deadly out to 600 yards (with 77 grain bullets). They don't make an optic for 7.62x39 (I'd stay with the AK-47 system if that were the case).

I am considering getting an AR-15. Price up to $1300-1600 is not an issue. The top of the list is the Colt 6920 because of the components, accuracy and reliability. I have received many recommendations for this rifle (including from guys in Afganistan who used theirs for 7 months in the field and some gun instructors). Recommendations for other rifles included a laundry list of required modifications. While not opposed to modifying the gun, I'd rather not if at all possible.

What other AR-15s perform at or above the Colt 6920's level with an ACOG? What modifications are required to attain this (if any)?

Are you dead set on a 16" carbine setup? I would think if you know most of your shooting will be at some distance, then why not look at a an 18" or 20" rifle system. You could always put a collapsible stock on an M16A4 clone, like I did, to shorten it up a bit.

If it must be 16", then you might also look at a BCM stainless barreled upper, if you're interested in wringing a little more accuracy out of it.

[TacMedic556]

I know this is a necro thread resurrection however some guys stop by and search or find these entries useful.

In using an ACOG TA01NSN on my 6920 with free float Centurion C4 cutout rail, I have found that the BDC (Bullet Drop Compensating) reticle works great on nearly every 5.56 load I have used. M193 and M855 show nearly no change that I can perceive out to even 450 meters. I spoke with Trijicon guys a few years back and they stated that the differences in 14.5 vs 16 inch barrels as well as bullet weights of 55, 62 or even 70 grains will only have an accuracy difference that is about the thickness of the reticle lines of the BDC reticles. Yes the reticle is designed for the 62 grain 855 load as stated above, however few of us will see the difference in shooting steel and using it. I zeroed mine with M855, however run everything in it and the accuracy in phenomenal.

Any ACOG on a 6920 will be awesome and run great.

[TehLlama]

I'd either go with the 6920 and the RCO-M4, or just accept that you might be willing to rock some newer stuff, and look more closely at something like the DanielDefense V5 and a variable powered 1-4x optic. What you get out of the DD and BCM options in the $400 more expensive range is usually a long (12" range) handguard, and options on barrels.

Otherwise, a Colt, especially with (down the road) a Centurion C4 cutout or FSP rail, is basically unbeatable for the price. M193 through a 16" barrel is absurdly close to the 62gr through a 14.5", and both of those are still hilariously close that the reticle isn't worth fussing over - my complaint with the RCO is the eye relief you get on that optic - this is where the various 1-4x optics really start to look more attractive to me, especially since you can, if you want more precision out of that rig, adjust the turrets and work on precision stuff that way instead of having to master the holdover/kentucky windage factor with the RCO. While it sounds like I'm not an ACOG fan - I am, but fixed optics, even with that glorious FOV, are still not as handy in most circumstances. I know I can make solid hits to 550yd with an M16A4/RCO-A4 pairing, but with choices on what to run I'd take my DD V5/TR24RT over my old issue weapon anyday.

The 6920, Aimpoint H-1 (or T-1), Centurion C4 FSP or Cutout Rail, and an X300 (or similar Surefire light) is probably the best overall setup you can run for under $2000, period. This leave some spare change to run a B5 SOPMOD or similar stock, maybe swap out the grip and trigger guard - but that with an aimpoint is a seriously stout rifle. If you want to really wring it out target shooting, go QD on optics, and just have a hunting scope you can swap over to it.

Functionally, the base 6920 keeps up with any non match ammunition. Free floating it helps slightly, but mostly rails provide you more useful room to control the rifle with a support hand, and maybe throw on a bipod. The handguard is the only major functional upgrade - everything else I listed is either an added capability (white light), or slight ergonomic improvement. A trigger (Geissele SSA) would also help accuracy, but again, not a critical change, the stock one works.

[C-grunt]

I have found my free floated 6920 to be really accurate for a non match barrel. My friend and I were shooting out at 350 ish yards today on a 2/3 sized metal silhouette. I was using my Colt/Aimpoint combo and he was using a DDV3 with an EOTech. Both rifles were able to ring the steel consistently at that range with cheap Russian ammo.

My next rifle is going to be a 20 inch with an ACOG but I agree that a Colt/BCM/DD with a good red dot is about the best all around rifle for under 2k

[Tzook]

I would say the Colt is one of the most bulletproof and fantastic rifles on the market, however while it's accuracy is acceptable if not good, you're looking at the wrong tool for the job. If you really want to reach out and touch something a carbine gassed Colt with a FSP is not what you need.

[Failure2Stop]

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