Colt 6520 Question

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Posted: 9/18/2005 12:13:57 PM EDT

The A2 Upper on this rifle is supposed to have M4 cuts to match with the M4 extension on the pencil barrel. Are the cuts made before the anodizing, as they are on the flat top M4 receiver or after?

Posted: 9/18/2005 12:37:06 PM EDT

[#1]

before

Posted: 9/18/2005 5:06:05 PM EDT

[#2]

I have two older ones that were made before, but three recently purchased ones were cut after, rather poorly, with no "4" marked on the front of the top receiver.

Posted: 9/18/2005 5:55:22 PM EDT

[#3]

Quoted:
I have two older ones that were made before, but three recently purchased ones were cut after, rather poorly, with no "4" marked on the front of the top receiver.

three rifles or uppers?

Posted: 9/18/2005 6:06:17 PM EDT

[#4]

Quoted:
I have two older ones that were made before, but three recently purchased ones were cut after, rather poorly, with no "4" marked on the front of the top receiver.

Sounds fishy. Did they come from reputable sources?

Posted: 9/18/2005 7:54:36 PM EDT

[#5]

I just got a 6520.

There is no "4" marked on the upper receiver. There is a "4" marked on the barrel or the barrel extension (can't remember). You can only see it if you take the barrel off, and that's when I noticed it.

The upper receiver is an A2, but it is cut for M4 ramps.

Posted: 9/18/2005 8:02:34 PM EDT

[#6]

Quoted:
I just got a 6520.

There is no "4" marked on the upper receiver. There is a "4" marked on the barrel or the barrel extension (can't remember). You can only see it if you take the barrel off, and that's when I noticed it.

The upper receiver is an A2, but it is cut for M4 ramps.

A "4" stamped onto the face of the barrel extension is a COLT M4 barrel extension

Is there anything stamped onto the front of the upper receiver, right above the gas tube hole ?

Posted: 9/18/2005 8:06:51 PM EDT

[#7]

I had one as described above, came from Specialized Armament,
had the 4 on the barrel extention, non anodized ramps and no 4 in the front of reciever,

Posted: 9/18/2005 8:49:17 PM EDT

[#8]

Three complete rifles from dealers in the reputable EE

Posted: 9/18/2005 8:53:14 PM EDT

[#9]

M4 ramps cut into the receiver are done during the machining of the receiver. They should be anodized just like the rest of the receiver.

Posted: 9/18/2005 9:01:17 PM EDT

[#10]

Quoted:
M4 ramps cut into the receiver are done during the machining of the receiver. They should be anodized just like the rest of the receiver.

One would think so.

Posted: 9/18/2005 9:46:37 PM EDT

[#11]

I think that Colt simply used parts on hand to put some of these together. The barrels/extensions were the M4 type, but the available uppers were not. So, they just took the standard A2 uppers they had at the time, dropped them back in the assembly line and cut the feedramps to match the barrels/extensions, but did not re-anodize them.

Posted: 9/19/2005 1:49:00 AM EDT

[#12]

i called Colt about the same problem with my new 6520 and was told that this did not sound right and to send it back for inspection. i have not sent it in yet but should be able to later this week. i will post an update when i hear back from Colt.

Posted: 9/19/2005 2:49:36 AM EDT

[#13]

this dosent sound right. I dont think Colt would do that. I would send it to them.

Posted: 9/19/2005 4:54:04 AM EDT

[#14]

Quoted:
I think that Colt simply used parts on hand to put some of these together. The barrels/extensions were the M4 type, but the available uppers were not. So, they just took the standard A2 uppers they had at the time, dropped them back in the assembly line and cut the feedramps to match the barrels/extensions, but did not re-anodize them.

I cant imagine COLT doing something like that...

Posted: 9/19/2005 9:29:35 AM EDT

[#15]

Quoted:
I think that Colt simply used parts on hand to put some of these together. The barrels/extensions were the M4 type, but the available uppers were not. So, they just took the standard A2 uppers they had at the time, dropped them back in the assembly line and cut the feedramps to match the barrels/extensions, but did not re-anodize them.

Agreed. My NIB 6520 is included in this description. The M4 feedramps were cut into the upper, not originally forged into it. They look ok for my taste, but I'm curious to hear how this pans out.

Posted: 9/19/2005 9:53:20 AM EDT

[#16]

I like Colt, believe they put out a quality product, and am not trying to bash Colt. Both of my AR's have Colt uppers. One is a 6520, and has the M4 feedramps done after anodizing.

But, this seems to be more than just one or two occurances and rifles/uppers with this trait seem to have come from more than one source, so I do not believe some unscrupulous vendor is behind it. I also recognize the demand for these LE/Mil rifles and do not find it unbelievable that any company would use whatever they have on hand in order to meet that demand, even Colt.

That said, I don't think these are defective uppers in any way, they were just modified to the new standard (M4) a little late in the assembly process.

BTW, my 6520 upper with un-anodized M4 feedramp cuts is running fine after a fair bit of use with no discernable wear to the feedramp cuts in the receiver.

Posted: 9/19/2005 1:10:42 PM EDT

[#17]

None of mine have feed ranps cut after anodising, all are before.

Posted: 9/19/2005 4:05:55 PM EDT

[#18]

Quoted:
Quoted:
I think that Colt simply used parts on hand to put some of these together. The barrels/extensions were the M4 type, but the available uppers were not. So, they just took the standard A2 uppers they had at the time, dropped them back in the assembly line and cut the feedramps to match the barrels/extensions, but did not re-anodize them.

Agreed. My NIB 6520 is included in this description. The M4 feedramps were cut into the upper, not originally forged into it. They look ok for my taste, but I'm curious to hear how this pans out.

All feedramps are cut into the upper. The question being presented is if they are cut before or after anodizing.

Posted: 9/19/2005 4:38:31 PM EDT

[#19]

Quoted:
Quoted:
Quoted:
I think that Colt simply used parts on hand to put some of these together. The barrels/extensions were the M4 type, but the available uppers were not. So, they just took the standard A2 uppers they had at the time, dropped them back in the assembly line and cut the feedramps to match the barrels/extensions, but did not re-anodize them.

Agreed. My NIB 6520 is included in this description. The M4 feedramps were cut into the upper, not originally forged into it. They look ok for my taste, but I'm curious to hear how this pans out.

All feedramps are cut into the upper. The question being presented is if they are cut before or after anodizing.

Right. And to clarify my theory a little more, I DON'T believe that Colt "dremeled" these uppers. I don't know very much about the machining involved for finishing an upper receiver forging, but I would assume Colt has a specific step in the process for uppers designated to be M4 uppers in which the CNC machine, or whatever, cuts the feedramps. These uppers were simply put back in and that step applied later than normal.

Posted: 9/19/2005 4:56:42 PM EDT

[#20]

My 6520 was made in May 2005 and the feedramps are shiny so they are cut after anodizing.

Posted: 9/19/2005 5:26:01 PM EDT

[#21]

Quoted:
My 6520 was made in May 2005 and the feedramps are shiny so they are cut after anodizing.

I don't know when mine was made ( sn: LGC 034XXX ) but the M4 ramps are shiny. No wear that I can see but I only have about 800 rounds through the gun at this time. I am not gonna sweat it unless I see it become an issue.

Also, for reference, I have no "4" marks anywhere on or in the upper or upper components.

Posted: 9/19/2005 5:44:44 PM EDT

[#22]

Just for refrence, here is a pic of the barrel extention of a 6320 M4 barrel, see near the ejecton port the "4" stamped
These reciever ramps were machined prior to anodizing, 6320 A1 reciever

Posted: 9/19/2005 6:50:17 PM EDT

[#23]

I talked to Ken Elmore at S.A.W. about this subject a few weeks ago concerning a late 90's LEO and he stated, "Colt actually cut hundreds/thousands of LE Uppers for the new feedramps after anodizing in the late 90's".

[ARCHIVED THREAD] - Colt 6520 Question

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