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M4A1 SOCOM BLOCK II 5.56 NATO STRIPPED UPPER RECEIVER

M4A1 SOCOM BLOCK II 5.56 NATO STRIPPED UPPER RECEIVER Reviews & Ratings

The Daniel Defense M4A1 SOCOM Block II Upper Receiver has been designed for those looking to match the specs and performance on the M4A1 SOCOM Block II carbines used by troops during Operations Iraqi Freedom and Enduring Freedom. The Daniel Defense M4A1 SOCOM Block II Upper Receiver features a quad-rail handguard equipped with a Picatinny-compatible rail sections. The barrel is cold hammer forged from mil-spec chrome-moly vanadium steel and features a SOCOM, heavy profile, with a chrome-lined interior, matching military-style barrels with the same construction. The gas block is a Daniel Defense pinned low profile block, the same as the current generation provided to SOCOM.


  • Choose upper receiver with or without a B5 SOPMOD stock.
  • Made from 7075-T6 aluminum
  • Barrel length: 14.5 inches
  • Twist rate: 1:7
  • DOES NOT include BCG, charging handle or flash hider


The Daniel Defense M4A1 SOCOM Block II Upper Receiver features a flat dark earth anodized finish.


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Reviews Summary
Customers rave about the M4A1 SOCOM BLOCK II upper receiver, praising its construction quality, accuracy, and robust build. However, many are disappointed with the missing M203 hangar kit, and some highlight cosmetic blemishes. Despite concerns over the upper's weight and certain design elements, most users agree it offers excellent value, especially for a heavy-duty choice.
What Reviewers Are Saying
Product Quality
75%
Many reviewers highlight the outstanding quality of the upper receiver, noting its solid construction, durability, and accurate performance. The precision of the barrel and the overall design contribute to a favorable perception of its build and utility.
Missing Features
40%
A common point of frustration among reviewers is the absence of the M203 hangar kit, which many expected to be included. This lack has led to disappointment, particularly for those intending to use specific accessories.
Cosmetic Issues
35%
Some customers report minor blemishes or imperfections in the anodizing and finish of the upper receiver. While these do not affect functionality, they contributed to some dissatisfaction regarding the product’s presentation.
Weight Concerns
30%
A number of users mention the upper's weight, suggesting it may not be suitable for everyone. Despite this, many appreciate that the weight provides stability and mitigates recoil, especially with the heavy profile barrel.
Value for Money
65%
Overall, reviewers consider the price of the upper to be reasonable given its quality and features. Many assert that it represents a great value compared to alternative options on the market, especially for serious users.
Customer Service Experience
25%
Customers generally express satisfaction with the service provided by Brownell's, praising their friendly and responsive support, particularly in handling inquiries and confirming orders.
4
Nice value, some nitpicks
BLUF: This upper represents a good value with a hammer forged Daniel Defense heavy barrel (not true SOCOM profile) and RIS II handguard. If you're looking for an out of the box clone correct upper this is not it. It would earn 5 stars if the receiver did not have DD's logo laser engraved on it and it had a true SOCOM profile barrel. The upper ships in a Daniel Defense box with a QC tag indicating date of assembly. The box was more than adequate to protect the upper in shipping. RIS II had the typical finish dings at the front end of the rail and it must be something that happens to every RIS II while being QC'd at Daniel Defense. The rail comes with the M203 hangers installed and rotated out of the way. If you're going to pin and weld I would recommend they be removed unless you plan to run an M203. Overall the rail is excellent. The upper receiver is decent. It has the look of being tossed in a box of upper receivers with small nicks in the finish. Nothing major and if you've handled new Colt receivers or military contract receivers you know they don't individually wrap these for storage. The machining on the receiver is excellent as is typical of Daniel Defense. The laser engraved Daniel Defense logo on the left side is really lame and I wish they would not do that. The barrel is a work of art in terms of finishing and machine work, as is to be expected from Daniel Defense. It is a heavy barrel but is NOT a true SOCOM profile ala Colt. Forward of the gas block is just a traditional HBAR profile. There are M203 flats cut behind the gas block so it could run an M203 with the RIS II. The low profile gas block is pinned with a taper pin. Gas port is military spec at .062" so it should run smooth. Overall this is a great value if you don't care about clone correctness and I would recommend it.
4
Dependable Upper
Mine came marked with the DD logo on the side of the upper. The two small scratches from anodizing on the end of the rail were much less noticeable than some of the other examples I've seen. I was somewhat disappointed that there was nothing protecting the muzzle and threads. The end of my barrel came with a scratch on the crown. Besides that the overall finish of the upper was quite good. As expected it shoots well and I've had no reliability issues.
4
Good overall
I had been waiting for it to come back in stock, great as always. Only complaint is the rail is a little off center.
4
Great, but not perfect
This upper will not take DDs own native BUIS flush at the front; it will either overhang by a length of one pic rail segment or you will have to back it off from the front by that same length - regardless it will not be flush with the front. This is due to the double pic segment at the front they have designated as a spot to say front sight here. This design is baffling to me that they would think this a necessity and the only reason I can think of for it is that these uppers were not designed with DDs BUIS in mind, but instead likely Knights Armament BUIS. Either way if you intend to use DD BUIS and you are OCD about fit it will bother you - if not then its no big deal. Other than this no complaints. A very solid out of the box upper. Pair it with a DD BCG and your choice of muzzle and charging handle to complete it.
4
Nick or ding on the same spot
As advertised, it does comes with the Colt style M4A1 heavy profile SOCOM barrel and as a bonus, it also has the M203 cuts. No M4A1 logo, but it does have Daniel Defense's logo laser engraved on the left front portion of the upper receiver. And, as always it has that ding/gash on the front top left portion of the RIS II rail, barrel facing you. Same exact spot from a previous DD M4A1 mid-length upper with 16" barrel and on another exact same spot on a DD MK18 stripped upper all purchased through, Brownells. Not an exact SOPMOD Block II non-FSP clone, if you're being nit-picky, but close enough for me to rest my leg and not worry about FOMO.