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Radical Firearms 5.56 Barrel Assembly Mid-Length - Zero Impulse Brake - 16"

Manufactured by Radical Firearms
Manufactured by Radical Firearms
13 Reviews

Out of Stock

NOTE: Limit 1 per household. Quantities exceeding 1 will not allow checkout.



Radical Firearms produces quality precision made barrels perfect for your next build or replacing an old barrel. Machined from 41V50 Chrome Moly Vanadium Steel and finished with a corrosion resistant Melonite. This exceptionally durable barrel has a bore that is harder than traditional chrome lining without the accuracy robbing side effects.

Chambered for the 5.56 NATO cartridge, with a button rifled 1:7 twist rate, this barrel will yield superior performance throughout the full range of .223/5.56mm ammunition, including the legendary 77-grain open tip match.

Includes a low profile set screw gas block, stainless steel mid-length gas tube, and Radical Firearms Zero Impulse Muzzle Brake.
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Barrel CoatingMelonite
Barrel ContourSOCOM
Barrel Length16
Barrel LiningMelonite
Barrel Material41V50 Chrome Moly Vanadium Steel
BrandRadical Firearms
Caliber Gauge5.56 NATO
Feed RampsM4
Gas Seat Diameter.750
Gas System LengthMid-Length
Manufacturer.Radical Firearms
Thread Pattern1/2 X 28
Twist Rate1:7

WARNING: This Product can expose you to chemicals which is known to state of California to cause Cancer and Reproductive Harm. For more information, see www.p65warnings.ca.gov

FYI, this is melonited stainless steel not sbn 4150

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An answer to a questions you might have buying this package. Yes, the gas block and muzzle device can be hand loosened so that they can be removed easily prior to installing the barrel on an upper receiver. I was worried myself, but had the tools if needed so I gave it a try.
<br>All in all a nice looking barrel, though the specifications need to be updated for this product. This is a stainless steel barrel with an exterior melonite finish including the threads and at the feed ramps and throat of the barrel. Still a good deal in my book. I'll update the review once I've been able to put some rounds through it.

Buy a brand with better QC


The SBN finish is terrible on this thing. Even the muzzle brake has brown runs in it. The barrel fades in and out from runs. Contacting PA to see about swapping.

Five Star Product

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I'm rating this 5 stars regardless of what shows up in the star count.
<br>Other reviews say some negative things that I didn't experience. My barrel combo was perfect ! Threads were good , coating and rifling look great. Barrel was dimpled for set screw. Packaged very well. A very positive experience for me. Comes with gas tube pinned to block and block slid on to the barrel to where it starts to get tight and the set screw is snugged to keep it from sliding but, is easily removed for barrel nut installation. Muzzle brake and crush washer are just hand tight. If caught on sale, it's a heck of a deal for a budget build
<br>As always BRAVO to Primary Arms for their FAST shipping and EXCELLENT customer service.

Five Star combo

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Not sure why the so so reviews for this combo. Bought on a sale and its a fantastic deal. Fit and finish were excellent. Shoots as good as it looks. Just cant beat it if you looking for a budget build combo and its on sale.
<br>They offer it without the muzzle brake and that's a heck of a deal. Cant touch that deal

Great Barrel


Excellent Barrel, I'm a gunsmith and have built many AR,s using different types of barrels and I will do the barrel break-in for the customer when they ask. I was very happy with the quality and very tight groups at 100 yards. Keep up the good work Radical Arms.

Hickups at first but works like a charm now

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wouldn't load a round out of any mag and would scratch the casing at first so I sent it back to radical and they gave us a new barrel super fast and were helpful and now it it's good to go and works amazing .

Great for budget build

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1 year and around 600 rounds. I’m happy! Can’t beat the price!

Doesn’t cycle steel case ammo

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When the barrel was first installed, it did not cycle with steel and brass case ammo. I found that the gas block was installed all the way to the little wall on the barrel, which might cause misalignment between the gas port and the gas block. So I listen the gas block, without much effort, and realign the gas block and loc-tite it. Second range trip, it cycles both Wolf gold and American eagle 5.56 with no problem and it locks back at last round. However, it just won’t cycle steel case no matter what I did to it. I guess I will have to run brass only with this barrel.

A good deal on a decent barrel

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Good barrel as far as I can tell after breaking in. Fit is good, no issues there and the price is excellent. My only reason for not giving it 5 stars is that I think the finish was less than ideal. The engraved marking near the muzzle is crooked, bu that’s purely cosmetic and not a show-stopper. I would buy again for a less expensive option build.

Great buy


Bought to replace a barrel on an old gun, was very affordable and easy. Once on out some round thru and it works like a charm no issues. Would us another with no problem.

Good Deal, Great Customer Service

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Barrel is accurate and balances nice. Muzzle brake and mid length gas system make for a very soft recoiling AR. Blow back from brake was barely noticeable. Cons: I had two issues. First was with muzzle brake timing and is minor. Using the supplied crush washer that came with this combo, I had to go up to almost 30ftlbs of torque to time it. That’s Higher than I‘d like. Including shims/peel washers vs a crush washer might have made it better, but for this price I could have bought those separately and still came out ahead. Second issue, the gas tube bend was out of spec. In my case this caused it to bind with the barrel nut, and not line up with the bolt carrier inside the receiver. I contacted PA about the issue and Tom took care of me without hesitation. He sent a new gas tube which corrected the issue. Again if it were not for the outstanding customer service of PA, I would have only given this product 3/5. Overall still very satisfied, Thanks again PA!

Mine arrived with no gas port but works well as a side charging bolt action range toy.

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Bought one of these back in May of this year. The barrel was nitrided stainless. Not a problem. However it came without a gas port. I initially contacted Radical for a replacement barrel, which I'm sure would have been provided, but then decided to keep it and make a bolt action AR. I did so with a side charging upper and it works just fine. It's a novelty at the range and is as smooth as silk with brass albeit a bit sticky occasionally when extracting steel cased ammo.

In love.

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500 rounds in, no complaints.