Colt A2 receiver question - Page 1

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[ARCHIVED THREAD] - Colt A2 receiver question

Posted: 3/5/2017 11:18:25 AM EDT

I am looking for a Colt A2 receiver with M4 ramps and found one marked with a 4 above the gas hole and anodized ramps and another with no "4" marking and ramps cut after anodizing and the seller says it was from a 6520 model carbine and and the ramps are Colt factory not a bubba job.. My question is would the 6520 be ok for a 727 clone? Anybody have comparison pics of these two Colt receivers ? Thanks

Posted: 3/5/2017 12:21:13 PM EDT

[#1]

Seller's wrong - unanodized ramps are bubba.

Posted: 3/5/2017 12:23:54 PM EDT

[#2]

Quote History

Quoted:
Seller's wrong - unanodized ramps are bubba.

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No, you are wrong. Colt put out a bunch of 6520s late in their production cycle with un-anodized ramps. Speculation is the uppers were originally made for rifles and the ramps were cut post anodizing.

OP, yes a 6520 upper would be fine for a 727 clone, the uppers are the same.

Posted: 3/5/2017 2:58:06 PM EDT

[#3]

Quote History

Quoted:

No, you are wrong. Colt put out a bunch of 6520s late in their production cycle with un-anodized ramps. Speculation is the uppers were originally made for rifles and the ramps were cut post anodizing.

OP, yes a 6520 upper would be fine for a 727 clone, the uppers are the same.

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This.. I had a 6520 with non anodized ramps

Posted: 3/6/2017 12:34:41 AM EDT

[#4]

Quote History

Quoted:

No, you are wrong. Colt put out a bunch of 6520s late in their production cycle with un-anodized ramps. Speculation is the uppers were originally made for rifles and the ramps were cut post anodizing.

OP, yes a 6520 upper would be fine for a 727 clone, the uppers are the same.

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SSeric02 hit the nail on the head on Colt using uppers with ramps cut after anodizing. But there are plenty of bubba jobs out there and you can tell because they Colt factory cuts on the 700 series carbines were much shallower than the deeper M4 type ramps.

Posted: 3/6/2017 12:54:40 AM EDT

[#5]

Quote History

Quoted:

No, you are wrong. Colt put out a bunch of 6520s late in their production cycle with un-anodized ramps. Speculation is the uppers were originally made for rifles and the ramps were cut post anodizing.

OP, yes a 6520 upper would be fine for a 727 clone, the uppers are the same.

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Correct lots of unanodized gov carbine uppers. And they normally look like pointy feed ramps

Posted: 3/8/2017 11:32:55 AM EDT

[#6]

Time to look at my Colt A2 to check for anodizing on the feed ramps

Posted: 3/8/2017 1:55:21 PM EDT

[#7]

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Quoted:
Time to look at my Colt A2 to check for anodizing on the feed ramps

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Have a feeling your OK, Bucket.

Posted: 3/9/2017 12:45:40 PM EDT

[#8]

That's right, you know something about that

Posted: 3/9/2017 1:03:57 PM EDT

[#9]

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Quoted:
That's right, you know something about that

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Posted: 3/10/2017 1:53:25 PM EDT

[#10]

My Colt 6520 circa early 2007. Un-annodized feed ramps.

Posted: 3/10/2017 4:06:28 PM EDT

[#11]

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Quoted:
My Colt 6520 circa early 2007. Un-annodized feed ramps.

http://i.imgur.com/fhZQnoH.jpg

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Does it have a 4 or M4 marking above the gas tube? The 6520 uppers that I have with anodized ramps are marked. Not sure about the manufacture date as the barrel doesn't have a date on my complete upper and the other was purchased with no barrel.

Posted: 3/11/2017 12:27:01 AM EDT

[#12]

Interesting.

I have a couple of 6520 uppers with barrels dated to 2003. They both have M4 ramps (not shallow) and are anodized. Raised C and keyhole forged. No F FSB.

Interesting that a posted above had an upper with a 2007 and non-anodized M4 ramps.

Posted: 3/11/2017 12:33:05 AM EDT

[#13]

I hypothogize that unless the receiver is marked M4 or 4, the receiver will not have M4 feed ramps cut. I have handled a number of uppers with feed ramp cuts, that were not marked with a 4 variation..... the feed ramp cuts in the receiver are much shallower and match the cuts of non-M4 barrels. They do not match M4 cuts at all. Two completely different animals.

It is interesting that early 727 and XM4 rifles had the shallow feed ramps, likely evolving into M4 feed ramps.... yet M16A2 rifles did not. Is it plausible to speculate that Colt initially added feed ramps into the receiver to facilitate feeding into earlier barrels, and then evolved into extended more aggressive ramps, machined into the barrel as well?