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  #1  
Unread 01-13-08, 05:46
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Odd unmarked bolt carrier in new Colt 6920

I just field stripped my new Colt 6920. I found the bolt carrier interesting. It is full auto M16 style (no surprise) however, no "C" mark. There is a nice peen mark from a hardness test in the rear and great staking of the gas key, but no C marking anywhere. Also, the bolt is marked "MPD" for Diemaco I assume. Anyone else seen this?

My other 6920 has the "C' on the carrier and "MPC" on the bolt. Just found it interesting, quality seems exactly the same. The upper on this rifle does not have a "C' either. Below the carry handle on the left is the keyhole mark, and to the right it has the Diemaco "D" symbol. It is marked M4 at the front under carry handle and has the T markings. The lower is out of Hartford, Conn, not Canada. The barrel is stamped C MP appropriately.

FYI, this dealer I bought it from is one of my best friends and holds an outstanding reputation, so I know it's legit. Anyone else have a 6920 like this? My other one with the C markings is of the same Colt order. The fit and finish on both are simply outstanding, not rough like everyone says about Colts. This Colt came with all the standard accessories, labeled box and plastic VCI type bag.

I just find the unmarked M16 carrier odd. I even looked under a magnifyer, no markings. The peen mark at the top rear is odd to. It's a pronounced punch mark. I can only assume a hardness test?

In any case, I lke the rifle. BOth of these 6920's are obviously well made and put together.
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  #2  
Unread 01-13-08, 08:53
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I saw a new 6920 last year that had a light gray color Diemaco M16 carrier, interestingly enough the upper receiver had a C and a Cerro forging mark.
The Diemaco carrier was lightly marked with the Diemaco symbol on the left side where the C would be. I've seen a few 6920 uppers that have the Diemaco mark on the upper receiver.
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  #3  
Unread 01-13-08, 09:12
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Quote:
Originally Posted by gotm4 View Post
I saw a new 6920 last year that had a light gray color Diemaco M16 carrier, interestingly enough the upper receiver had a C and a Cerro forging mark.
The Diemaco carrier was lightly marked with the Diemaco symbol on the left side where the C would be. I've seen a few 6920 uppers that have the Diemaco mark on the upper receiver.
Interesting, so they are out there. I guess the thing I'm most curious about is the lack of markings on the carrier, and the hardness test evident by the pronounced peen mark on the top rear of the carrier.

I heard the Diemaco marking was hard to see, so I looked under magnification and no marking. Do you folks agree the punch mark is a hardness test on this carrier? I've seen hundreds of bolt carriers both in and out of the military and never noticed the punch mark.

Going by the fact I have a Candian upper receiver and bolt, I can only assume this is a Canadian carrier as well, just unmarked. It's color is a close match to the MPD marked bolt. In any case....these Colt's are nice weapons.


I need to get out there and shoot this thing.....
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  #4  
Unread 01-13-08, 13:36
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Have seen new military Colt m4a1's with Diemaco marked BCGs. The triangular shaped stamp.

I don't know enough about the varius markings on upper reciever to comment.
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  #5  
Unread 01-13-08, 13:51
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The only thing consistant about Colt is inconsistancy.
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  #6  
Unread 01-13-08, 15:09
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Diemaco bolt carrier group below, this one from a batch of 6520s. Also seen in a mid-2007 6920.

jar420- Does your bolt have numbers below the MPD?





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  #7  
Unread 01-13-08, 19:55
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Quote:
Originally Posted by Skintop911 View Post
Diemaco bolt carrier group below, this one from a batch of 6520s. Also seen in a mid-2007 6920.

jar420- Does your bolt have numbers below the MPD?





Well, my bolt is identical to yours, numbers and all. However, I wish I had your carrier. I have the Franken carrier, unmarked with the huge punch mark in the rear. Not sure about my carrier, I may call Colt tomorrow to confirm it's one of theirs. I suppose the Carrier could have been messed with/swapped before arriving at my shop.

Thanks for sharing the pics! Your carrier doesn't have a punch mark at the top of the rear half does it?
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  #8  
Unread 01-13-08, 21:40
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Quote:
Originally Posted by jar420 View Post
Well, my bolt is identical to yours, numbers and all. However, I wish I had your carrier. I have the Franken carrier, unmarked with the huge punch mark in the rear. Not sure about my carrier, I may call Colt tomorrow to confirm it's one of theirs. I suppose the Carrier could have been messed with/swapped before arriving at my shop.

Thanks for sharing the pics! Your carrier doesn't have a punch mark at the top of the rear half does it?

If your gun was new, and in all the proper packaging, it's probably a legit carrier. You're more likely to see people raid your bolt, buffer, or FCG than the bolt carrier.

I don't recall if the punch mark is there or not. I've seen what you're talking about, but can't tell you on which guns or when. I'll look when I see the Diemaco guns again.
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  #9  
Unread 01-13-08, 22:13
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Sounds good, and good point about the bolt carrier not being a hot item for robbing, I didn't really look at it that way. Thanks again for the help!
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  #10  
Unread 01-14-08, 00:21
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Your gun is factory.

I've seen another few carrier that have that dimple on the rear.
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  #11  
Unread 01-14-08, 06:26
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Quote:
Originally Posted by scottryan View Post
Your gun is factory.

I've seen another few carrier that have that dimple on the rear.
Thanks Scott!
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  #12  
Unread 01-14-08, 06:29
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Quote:
Originally Posted by scottryan View Post
Your gun is factory.

I've seen another few carrier that have that dimple on the rear.
My recent 6920, Colt Defense Mfg


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  #13  
Unread 01-14-08, 08:45
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Quote:
Originally Posted by Paladin View Post
My recent 6920, Colt Defense Mfg



You guys rock. Mine is just like this, only no "C" mark. The dimple is identical however.

Thanks again.
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  #14  
Unread 01-14-08, 19:14
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No problemo. Our last batch of Dept 6520's are a mix of Dimeco and Colt Defense parts. That pic was my personal 6920.
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  #15  
Unread 07-28-11, 17:02
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Question How about this?

I got a BCG like the one jar420 has, except mine has:

-no dimple(hardness test mark)
-no C or D stamped on side
-bolt is stamped MP on top and AM stamped on bottom.
-also carrier is full auto

Can someone tell me if this is Colt and or Diemaco?

BCG came from a supposedly and hopefully a factory colt 6920 upper.

I verified the barrel is Colt per:
-C MP stamp
-white paint near barrel nut
-4 stamped on barrel extention

And I verified the receiver is Colt/Diemaco per:
-D and A slashed stamped on side
-M4 stamped above gas tube

Please let me know, appreciate any replies
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  #16  
Unread 07-28-11, 17:08
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Quote:
Originally Posted by startedwith1 View Post
I got a BCG like the one jar420 has, except mine has:

-no dimple(hardness test mark)
-no C or D stamped on side
-bolt is stamped MP on top and AM stamped on bottom.
-also carrier is full auto

Can someone tell me if this is Colt and or Diemaco?

BCG came from a supposedly and hopefully a factory colt 6920 upper.

I verified the barrel is Colt per:
-C MP stamp
-white paint near barrel nut
-4 stamped on barrel extention

And I verified the receiver is Colt/Diemaco per:
-D and A slashed stamped on side
-M4 stamped above gas tube

Please let me know, appreciate any replies


Hmmm. Your BCG sounds like an LMT. Got any pics.

C4
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  #17  
Unread 07-28-11, 18:01
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here's some, hope it helps







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  #18  
Unread 07-28-11, 18:25
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Looks like an LMT to me. At least the bolt does anyway.

Last edited by spamsammich; 07-28-11 at 18:26
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  #19  
Unread 07-28-11, 19:06
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Thanks for the quick replies. So possible a LMT at least the bolt. May I ask why it could be LMT?

Anyone on the carrier? I can post more pictures if need a specific angle.

You guys are awesome!
By the way I'm new here, just let me know what I can do to make things better.
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  #20  
Unread 07-28-11, 19:14
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Stress relief cut underneath the lugs of the bolt and the markings. LMT does both of those things. Nobody else does as far as I know.
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