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Daniel Defense DDM4 300 S, URG, 10.3in, 300 AAC Blackout Complete Upper Receiver w/ Flash Hider
As Low As $1,109.00 Save Up to 24%
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Most Helpful Positive Review DD is the best
I love Daniel Defense products and customer service. Would recommend to anyone looking for a quality AR-15, and parts. There a quality product produced in the good ole USA. Now they want this review to 200 words so this sentence should be sufficient.
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Daniel defense 300 blackout 10.3

by red93cobra, Verified Owner from CO, United States Written on December 18, 2024
I will admit I am a little biased, I have a few Daniel defense rifles and they are worth every penny. Sub MOA at the range. Can’t wait to try out this upper.
Would recommend: Yes
Was it helpful to you? Yes | No

DDM4 300 BlkOt Upper

by Blues2boogie, Verified Owner from MO, United States Written on December 17, 2024
Great product, price, and I received the product within approximately one week from Optics Planet.
Would recommend: Yes
Was it helpful to you? Yes | No

Variety is the Spice of Life

by dbank57, from SC, United States Written on December 12, 2024
I purchased this upper to go on my DD M4V7, which is chambered in 5.56/.223. Coupled with the Law Tactical folding stock adapter, it allows me to convert my carbine into a PDW/truck gun with enough power to punch through windshield and other tempered glass.

The upper is OEM, so there is really nothing else necessary to say about it. The upper fit perfectly and operates flawlessly.
Pros:
  • OEM direct replacement
Cons:
  • None especially at price point
Best Used for:
  • PDW, home defense, truck gun
Would recommend: Yes
Was it helpful to you? Yes | No

Good purchase

by CF, Verified Owner from TX, United States Written on November 23, 2024
Great upper. All the quality you expect from Daniel Defense, a little pricey but you get what you pay for. Optics planet offers a decent discount on it if you are patient.
Would recommend: Yes
1 of 1 found the following review helpful.
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great upper

by Pablo Coloma, Verified Owner from FL, United States Written on November 10, 2024
I have a 5.56 rifle I was surprised for his performance. I decided to order a 300 blackout upper you will not be disappointed it shoots pretty smooth I’m very happy with this purchase. I’m planning to change the muzzle device with a Surefire to combine with my suppressor .
Would recommend: Yes
Was it helpful to you? Yes | No

Couldn't be happier!

by Stewart, Verified Owner from GA, United States Written on September 2, 2024
Replaced the flash hider with a SilencerCo ASR muzzle brake, then installed the upper onto a registered SBR lower. I ran several different types of 300 Blackout ammo through it including Winchester, Sig Sauer, Fiocchi, and PPU, and several different bullet weights from 110 grain supers to 220 grain subs. All cycled flawlessly, all locked back on the last shot, no matter whether I was shooting supers or subs, suppressed or unsuppressed. FWIW I was using a carbine spring and carbine buffer. Simply put, I could not be happier with this Daniel Defense 300 Blackout upper. Paired with a SilencerCo Omega 9K suppressor, I think I just found my new favorite firearm.
Pros:
  • durable
  • reliable
Cons:
  • Expensive
Best Used for:
  • Home Defense
  • range & target shooting
Would recommend: Yes
Was it helpful to you? Yes | No

amazing price

by king, Verified Owner from NC, United States Written on August 21, 2024
Amazing price. Can’t beat a DD upper for the name and quality for the price.
Will be buying from here in the future.
Would recommend: Yes
1 of 2 found the following review helpful.
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300 Black that just works - Supers and Subs

by clickhouse, Verified Owner from NC, United States Written on July 18, 2024
This is a great deal. This is a very high-quality DD SOCOM-MK18 upper chambered in 300 Blackout. A MK 18 retails from DD for $2,200. The math is simple: pair this with a very high quality lower and use the savings to buy ammo.

It is heavy because of the pic rails on top, bottom, left and right, but that doesn't bother me. The bird cage flash hider works well, but let's be honest you're going to be shooting this suppressed. And the really good news is that, in my experience, range and match supers and subs cycle fine with a suppressor. I haven't had to make a change to the buffer assembly and haven't had to consider an adjustable gas block. It just works.
Pros:
  • value
  • Build quality
  • Works 10/10
Cons:
  • Heavy
  • Ammo costs
Best Used for:
  • home defense & plinking
Would recommend: Yes
1 of 2 found the following review helpful.
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DDM4 300S 10.3 Upper Receiver group

by Rob, Verified Owner from TX, United States Written on July 7, 2024
It's a MK18 in .300BLK, product was obviously perfect because Daniel Defense QC is among the best in the business. If you want a very reliable and durable shorty upper in .300BLK, there are not many options better than this.
Pros:
  • Durability
  • Reliability and ease of use
  • QC
Cons:
  • weight
  • cost
Would recommend: Yes
1 of 1 found the following review helpful.
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the best!!!

by Corey, Verified Owner from OH, United States Written on April 14, 2024
Daniel defense always puts out a solid product. You can always trust what they put out!
Pros:
  • solid
Cons:
  • None
Best Used for:
  • Self / home defense
Would recommend: Yes
Was it helpful to you? Yes | No
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