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M4 LE6921EPR Upper Group 14.5in with BCG

M4 LE6933 EPR Upper Group 11.5in with BCG.

M4 LE6933 EPR Upper Group 11.5in Stripped

COLT - M4 ENHANCED PATROL RIFLE 5.56 UPPER RECEIVER GROUPS

6 Reviews

Barrel Length

16.00
14.50
11.50

Receiver Style

Complete
Stripped

Brownells #

160000505, 160000506, 160710150, 160710151

MFR #

LE6920EPR-CK, LE6921EPR-CK, LE6933EPR-CK, SP402307

UPC

098289035493, 098289035509, 098289035516, 098289600158

$729.99 - $999.99

Purchase Limit

Out of Stock

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Can we ship this to you? (US only)

How To Buy Guns Online

International purchase information

What is the COLT - M4 ENHANCED PATROL RIFLE 5.56 UPPER RECEIVER GROUPS?

The Colt ERP, or Enhanced Patrol Rifle, line of M4 Upper Receivers that come with Centurion Arms free float M-LOK® handguards, making for a convenient and practical upper receiver ready to drop on your AR-15 lower receiver.

Available in 3 different barrel lengths, each is chrome lined, has a 1-7 twist, is button rifled, and has a phosphate finish.

You can also choose between complete, which includes a M16 bolt carrier group and charging handle or stripped which does not include those items.

All NFA rules apply.

See all of our AR15s and AR15 parts here.

Available options

Image	Description
	M4 LE6920EPR Upper Group 16in with BCG UPC: 098289035493
	M4 LE6921EPR Upper Group 14.5in with BCG UPC: 098289035509
	M4 LE6933 EPR Upper Group 11.5in with BCG. UPC: 098289035516
	M4 LE6933 EPR Upper Group 11.5in Stripped UPC: 098289600158

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Choosing a Brownells Featured Dealer is the fastest and easiest way to complete your purchase. Brownells Featured Dealers have agreed to perform FFL transfers on guns purchased online from Brownells. We have their necessary FFL information on file and your FFL order will ship directly to them once processed.
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M4 ENHANCED PATROL RIFLE 5.56 UPPER RECEIVER GROUPS REVIEWS

5.0

6 Reviews

5 Stars

100%

4 Stars

3 Stars

2 Stars

1 Stars

Reviews Summary

Overall, customers rave about the Colt M4 Enhanced Patrol Rifle upper receiver for its excellent quality, fit, and accuracy. Many users report impressive performance and recommend it for builds, although some mention typical fitting adjustments. The reviews highlight its potential for accuracy even at long ranges, suggesting it's a solid investment for enthusiasts.

What Reviewers Are Saying

Product Quality

100%

Reviewers consistently emphasize the high quality of the Colt upper, noting its excellent fit and finish. This quality is a significant deciding factor for customers considering this product, establishing Colt's brand reputation for reliability.

Accuracy

80%

Many customers are impressed by the accuracy of the upper, with one reviewer stating it allows for consistent shooting at extended ranges. This highlights the upper's performance, making it appealing for serious shooters looking for precision.

Build Experience

40%

Some reviews mention the experience of fitting the upper to different lowers, with minor adjustments required. This reflects a typical hands-on build experience associated with AR platforms, indicating that users are comfortable with customization.

Recommendation

60%

Multiple reviewers recommend the Colt upper for anyone seeking a high-quality and accurate AR build. This positive sentiment suggests a strong community trust in Colt products, further encouraging potential buyers.

Performance at Range

60%

The upper's ability to perform well at longer distances is frequently mentioned, showcasing its capability in various shooting conditions. This aspect appeals to shooters looking for versatility and reliability in their firearms.

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A Complete Package

This is a complete package and was well worth the wait of 6 months on waiting list. Just removed the 20" upper from Bushmaster rifle and dropped this one into place. added a set of Magpul popup sights, performed function tests and it was range ready

Would you recommend this? Yes, I would recommend to a friend

by JOHN GORDON on April 07, 2026

Verified Purchase

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Outstanding Value & Prompt Delivery

Typical Colt quality, fit and finish.

by JOSE LUCIANO on December 28, 2024

Verified Purchase

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Colt upper

Looks good like you would expect from Colt. Haven’t finished the build yet, so I haven’t tried it out yet. Would recommend so far.

by JAMES ALM on April 14, 2024

Verified Purchase

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Colt 6921

I bought this Colt upper because of the 14.5" barrel and I pinned and welded the flash hider, so it is 16.1" overall length. It seems to be perfectly gassed as it tosses brass 3 feet away at the 4 o'clock position. What amazed me the most about it was the accuracy of this upper, I have 4 other AR's and this is easily the most accurate of them all. Mine has no "C" code marked on the receiver, but the barrel and bolt are properly marked. I recommend this if someone is looking for a quality and accurate Colt upper that will last a lifetime, it's a good quality item.

Love it

Really cool upper to make an SBR with. I have an older M4 colt, I had to buy some accu wedges to make a perfect fit, but that's pretty normal with any AR IMO.

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COLT - M4 ENHANCED PATROL RIFLE 5.56 UPPER RECEIVER GROUPS

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M4 ENHANCED PATROL RIFLE 5.56 UPPER RECEIVER GROUPS REVIEWS

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