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Radical Firearms 10.5 in. 5.56 M4 Upper Assembly
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Most Helpful Positive Review Fit-n-finish, accuracy, Mil-Spec, Love it
I was building a budget AR pistol. I've built 16in ARs, but never an AR pistol. Built the pistol on an Anderson lower receiver. Because this build was based on a low budget, I located this lower assembly based on price comparison and features. The upper assembly came minus BCG and charging handl...
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Most Helpful Negative Review Fair upper
I purchased t bu is upper to complete my work gun. Everything works great and I do like it. However there is a problem with the barrel I encountered. While going through armored course I gauged the barrel and it is not 5.56 even though its stamped that way. Had few ppl check it since and they c...
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Radical Firearms upper

by Dale, from CT, United States Written on January 24, 2023
This is my fourth Radical Firearms upper that I’ve purchased in two years and you cannot beat the quality for the price. No it’s not Daniel defense but it is a fraction of the price but don’t let the price deceive you you get great value for the money.
Would recommend: Yes
1 of 1 found the following review helpful.
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10.5 W/ Full Quad Rail - Ok but not great

by Toby, Verified Owner from MO, United States Written on September 14, 2022
It would be a nice quad rail if the QD mounts worked with any of my Magpul 2 point QD slings. The QD mounts do not bite into this FQR and pull free with a little tug. Might be able to fix and make it usable but we will see. Specs say the quad rail is 14.88 OZ but feels heavier. Bought this when Optics planet had it on sale and advertised as 4150 CMV, found out afterwards it is only 4140 CMV. Meh... Bottom line, it is OK well built for the price and what it is built with, but not great.
Pros:
  • Built well
Cons:
  • Heavy, QD mounts on FQR
Best Used for:
  • Target shooting
Would recommend: No
Was it helpful to you? Yes | No

Great Product

by ForestRangerJoe, from SD, United States Written on April 20, 2019
Put it on a firearm I was re-building and works great.
Fit perfectly on my lower and couldn't ask for a better product.
Shipping was impeccable and it arrived on schedule.
I will definately buy more products from Optics Planet as I feel they offer great products at great prices.
Would recommend: Yes
1 of 1 found the following review helpful.
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Great pistol upper

by Robrob, Verified Owner from LA, United States Written on April 27, 2018
Really nice upper. I liked the one with the m lok best. A nice slim feel to it. Everyone that handles it likes the balance with the SOB arm brace. Best one for the money anywhere. Can't go wrong here.
Pros:
  • Price , Quality
Cons:
  • None
Best Used for:
  • Pistol or SBR
Would recommend: Yes
2 of 3 found the following review helpful.
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Retired Vietnam vet

by Colin, from GA, United States Written on November 29, 2017
I'm please service was fast wish They Carried 9mm lower though nothing else needs to be said will continue to purchase as needed in the future find a cheaper to buy upper and lower rather than complete firearm
Would recommend: Yes
1 of 7 found the following review helpful.
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