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Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper CTSP63528 Caliber: .223 Remington, Muzzle Device: No, $3.01 Off w/ Free S&H

Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
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Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
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Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
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Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
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Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
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Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
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Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
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Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
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Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
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Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
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Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
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Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
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Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
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Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528
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Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528

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Questions & Answers
Will this be "C" stamped? Also, which forge markings do these have?

No, there are no Colt proof marks on this upper. The forge marking is a Square (Brass Aluminum Forging Enterprises). Save your money can get a real Colt upper if you're after the markings.

by Drew Austin, Verified Owner, April 1, 2019
See 1 More Answer
Does this upper have the colt cage code marking 13629 on it? Expert Answer

No, it may or may not include the cage code. Unfortunately, Colt has not included it on all of the uppers.

by Kurt Colbourne, Gear Expert, October 7, 2021
View All Q&A You Have a Question? Ask!
Customer Reviews
Helpful Positive Review
It happens when you deal with Colt by SC23, April 18, 2019
I want to preface this by saying that I did not buy my upper from Optics Planet, but instead received it through RSR and it was the exact same way. No "C"; no cage code... just the square forge mark. This upper actually came in a group of uppers th...
Read More...
9/9 found this helpful
Helpful Positive Review
Not Stamped How I'd Like, But Its the Real Deal by Colt AR Collector, Verified Owner, November 15, 2019
Colt as of late has really cut back on stamping their parts with the famous "C". Since Colt announced they were abandoning the civil market, I bought two of these from Optics Planet. No C stamping, but there was a cage code on both receivers. Also, t...
Read More...
2/2 found this helpful
Helpful Positive Review
Real deal colt upper by Aquajoe182, March 16, 2020
The upper I received is current production square forged colt upper. Complete with dry film, white T marks and M4 feedramps. It does have cage code, but no C stamp, which is not a deal breaker. If your looking for a “proper” marked colt upper, this i...
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1/1 found this helpful
Helpful Positive Review
Colt Upper by Jake, Verified Owner, April 20, 2020
I know Colt has been inconsistent lately with their markings but mine came stamped with their cage code. Its not the colt "c" stamp, but I actually like the look of the cage code better. The anodizing is good, but the black dye didn't quite get into ...
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1/1 found this helpful
Helpful Negative Review
Deceptive picture by GN, Verified Owner, June 20, 2025
The receiver I got only has a Forge mark + M4 Feed. No C mark or cage code. Don't buy it if you want a classic "Colt" upper.
1/1 found this helpful
Most Recent Reviews
Key forge blank upper by Izzy, Verified Owner, May 13, 2025
Received this upper today assuming it would have a cage code being that all 3 colt rifles I've purchased recently came with a cage code. I doubt this is a real colt part wasted money
Read All 10 Reviews
Caliber:
.223 Remington
Muzzle Device:
No
Finish:
Matte
Color:
Black
Condition:
New

Code: 14J-URC-RS423-CTSP63528

MPN: CTSP63528

List: $179.00Save $3.01
$175.99

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OP Bucks$4.53

Product Info for Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper

Upper, 223REM/556NATO, Black Finish, Dust Cover, Forward Assist, M4 Feed Ramps SP63528image

WARNING: California`s Proposition 65

Specifications for Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper:

Manufacturer: Colt
Caliber: .223 Remington
Muzzle Device: No
Finish: Matte
Color: Black
Gun Model: M4
Condition: New
Magazine Included: No

Package Contents:

  • Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper

What firearm models does the manufacturer say Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper is compatible with?

The manufacturer suggests that Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper is compatible with M4

Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper Orderable Models

List of Orderable Models

  • Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528 , MPN: CTSP63528 , Code: 14J-URC-RS423-CTSP63528

Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper Unavailable & Discontinued Models

List of Unorderable Models

  • USED, Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528 , MPN: CTSP63528-EDEMO , Code: 14J-URC-RS423-CTSP63528-EDEMO-DF-C
  • USED, Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528 , MPN: CTSP63528-EDEMO , Code: 14J-URC-RS423-CTSP63528-EDEMO-US-C
  • USED, Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528 , MPN: CTSP63528-EDEMO , Code: 14J-URC-RS423-CTSP63528-EDEMO-IN-D
  • USED, Colt 223 Rem/ 556 NATO M4 Feed Ramps Upper, Black, CTSP63528 , MPN: CTSP63528-EDEMO , Code: 14J-URC-RS423-CTSP63528-EDEMO-RE-B
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