Late last year I bought a Colt 6960 upper receiver group (stripped - no bcg, no charging handle) from Brownells. It had a defect (barrel extension's feed ramps weren't cut deep enough, it was kind of half-way between rifle and M4 cuts and did not meet the feed ramps in the upper receiver) and I sent it back to Colt for repair; they sent it back repaired - WITH a bolt carrier group, and with a charging handle. I wasn't gonna look a free Colt BCG gift horse in the mouth I popped the bolt out, dripped a drop of lube on my finger and lubed the bolt ring where it rides in the carrier, wiped down the rails where the carrier rides in the upper, and went to the range. I put I think a couple of mags through it on it's maiden voyage and cleaned; replaced the muzzle device with a suppressor mount and had it back to the range today. First mag unsuppressed went great - on round 21 of being suppressed, it ate a gas ring:



So to recap - 90 rounds unsuppressed (plus the unknown number of rounds Colt ran through it to verify they fixed it; it came to me a little dirty), then 21 rounds suppressed - all M193 clone or M855.

I decided to inspect it when I got home, and replace the rings...

The carrier is unmarked - no C, no cage code, no nothing
So's the bolt; no MPI markings, no nothing

I went to check the inside of the carrier where the bolt rides and uh...it's not chrome lined. I compared it to a couple of Colt M16 carriers (bought from CDNN in the early 2ks; they came with red extractor inserts, thats how old they were ) and the finish seems much smoother - if I had to bet, I'd say the new carrier was nitrided. I have a couple of Colt half-moon 6921 carrier groups as well and those are marked C, bolt is MPI, etc etc etc...

Is Colt actually nitriding carriers (and bolts) now?? Or is this something they only sent with the 6960 CCU rifles, or....??? I'm really puzzled by this

I'm half considering putting this in a baggie and putting it with the original box, and buying a different BCG for it since there's nothing on it that says Colt, and I'm not even sure it's "legit" at this point even if it did ship from Colt to me this way...

Wonder if it's just a test bolt since you didn't send yours in and they forgot to remove it before it was sent back to you.

Likely scenario.

Possibly...it was for sure tested with it, but it was also lubed up, packaged, etc. I'm thinking they just assumed it was a complete upper (even though it wasn't as sold) so they shipped it back as a complete upper.

Either that or they were contrite and wanted to make it up to me?

Edited to add - it'd be really weird though if that was what they used to test, since they could have thrown in a mil-spec chromed carrier since I'm sure they're laying around? That's kind of my question - I'm wondering what 6960s came with as complete rifles or uppers now...I'm wondering if that was what they shipped with originally?

Nitride carriers aren't bad or anything - it's just a departure, so...just looking for more info.

Park varies from dull to shiny black. Markings/lack thereof varies as well.

I've seen some Colt carriers where they definitely look nitrided at first look, deep black and shiny.

Never once seen a Colt carrier unlined.

As to what you received and the back story , hard to say.

Yes, I have a bunch of Colt BCGs, all phosphated...and this one does not feel like any of them, inside or out. Hence the question - what's Colt shipping now; did I get a one-off weird one, or is Colt shipping Nitride carriers in certain uppers/rifles?

Having a Colt carrier or bolt with NO markings at all, without any of the roughness of phosphating, and no chrome on the inside at all...very weird.

If it's not a Colt BCG, then how did it get to me in a Colt upper, shipped directly from Colt...

Is the inside of the gas key chrome lined? Nitride carriers usually have a nitride finished gas key as well with no chrome on the inside.

No chrome lining anywhere

In the OP man.

Is it? I went and read over it twice before I even hit submit. I see where he said the carrier isn’t chromed, but didn’t see any mention of if the gas key was chromed or not.

Sounds like a nitride carrier then… Very odd coming from Colt.

Any pics of the carrier?

It looks like literally every other carrier on the earth, except for some of the weirder ones...



Staking is pretty shit though, THAT does not look like any of my other Colt BCGs...

Same dark phosphate as many recent carriers/bolts.

Example of a Colt bolt from last year:

Attached File

Thank you for posting the pictures. It appears there is no chrome lining of the carrier or key, like you stated from these pics at least. Never seen a Colt with no chrome lining.

Did you think I was lying or making this up or something?

I haven't either, hence the point of this thread in the first place...are recent Colts coming with these bolts/carriers, or what?

NO, I believe you, just wanted the pics for my folder, I like to save stuff like this.

I have a LOT, lot of Colts, almost 30, none of my carriers look like that lacking the chrome lining..

I purchased a 6960 (complete rifle) in June of last year; the BCG that came in it is phosphated with C marked carrier and MPC marked bolt-identical to the BCGs that came with my 6920 and 6940. All are also chrome lined.

I suspect, but can't say for sure, that Colt BCGs are OEM'd by Microbest just based on their appearance. I have never heard of nor seen a Colt with a nitrided BCG.

Ahh! Gotcha...keeping track of the oddities, that makes more sense

Yours is the only one that I've heard of.

I've handled north of 75 Colt rifles in the past ~2 1/2 years, and own plenty , not once have I come across one without the carrier interior /gas key hard chromed.

Was not my intent to insult you, if I came across that way my humble apologies.

Yeah, could be - when I get a chance I'm going to give this another shot at the range, suppressed and unsuppressed. If the same thing happens again with a blown out gas ring, I'll just bag it up and put it with the original charging handle that came with it (I replaced it with a BCM), put it back in the shipping box, and replace it with a chrome Microbest anyway. The lack of chrome linings makes me a little skeeved out in the first place - and the crappy un-Colt-like gas key screw stakings doesn't make me super happy with it as well.

The more I think about it, the more I think I'm just going to replace it with a Microbest or Toolcraft anyway...why wait to see if it fails when I don't need to

Colt used to make part of their BCG in house. Not sure if it’s still a thing today.

AO Precision is one of their OEM supplier as clearly stated on their webpage

Exactly - from 2000/2001 onwards until now I've had maybe 20 or so BCGs go through my hands, none of them looked like this, not from Colt. Like someone mentioned maybe it came from a testing fixture at Colt, but why would they use something like this...shrug. I don't have any "new" Colt BCGs, from within the last 5 years - save this one, which is an oddity for sure.

All good! A little context cleared it right up - thank you!

That's probably what I'd do.

TBH, if I saw someone selling the BCG pictured in your post, I would not believe it was a Colt.

Yeah, that's why I was asking - I wouldn't have believed it either...but that's what they sent it to me with. Now I kind of wish I had photodocumented opening the box up and all it's parts, etc...oh well.  The bolt carrier notwithstanding, the fact that the bolt isn't marked MPI or anything - I'm not even sure it's a C158 bolt! I'm kind of wondering if this was a leftover from when they licensed out some other manufacturers (like the early Colt Competition ARs) and they had a bunch of weird bcgs left behind...who knows.

Anyway, chrome Microbest on order from WCArmory - it'll clean up easier after shooting suppressed anyways

Why not reach out to Colt CS and bring it to their attention? Tell them you sent an upper and they returned it with a bizarre out of spec bcg.

"Hi Colt, I sent you an upper without a bolt carrier group, and you sent me back an upper WITH a bolt carrier group, but it's a weird group"

...

Yeah I probably wouldn't bother bringing it up to them.

I have Sionics NP3 BCGs in my 6940 and 6960 just because. I keep the takeoff C/MPC marked BCGs as spares.

If you were honest you would tell them.

You're saying "if you were honest, you'd tell them and then demand a new bolt and carrier to replace this weird one"? Uh...yeah....no

I'm putting it back in it's original shipping box and leaving it there, and buying a new BCG to use for it.

No, what I'm saying as I understand your OP, is that Colt inadvertently sent you a BCG and charging handle you did not request or pay for.  Keeping the BCG and CH is dishonest and you know that!

In addition, you are "pissing and moaning" it is not a Colt BCG.

I would imagine that Colt would appreciate the heads up and just say "keep it."  Either way, that would be the honorable and right thing to do and you know that!

I never mentioned anything about demanding a new BCG.  You should have called Colt ASAP and you know that!

But, you do you.

That’s exactly what I would do.