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AR57 ULT 12in Barrel 5.7x28mm Upper Receiver Assembly AR57ULT-12 Caliber: 5.7x28mm, Overall Length: 24.5 in, 13% Off w/ Free S&H

AR57 ULT Upper Receiver Assembly, 12in Barrel, 5.7x28mm Caliber, AR57ULT-12
AR57 ULT Upper Receiver Assembly, 12in Barrel, 5.7x28mm Caliber, AR57ULT-12
AR57 ULT Upper Receiver Assembly, 12in Barrel, 5.7x28mm Caliber, AR57ULT-12
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AR57 ULT Upper Receiver Assembly, 12in Barrel, 5.7x28mm Caliber, AR57ULT-12
AR57 ULT Upper Receiver Assembly, 12in Barrel, 5.7x28mm Caliber, AR57ULT-12
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AR57 ULT Upper Receiver Assembly, 12in Barrel, 5.7x28mm Caliber, AR57ULT-12

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Questions & Answers
Is the length of the 12" barrel include the muzzle brake or is it a 12" barrel + whatever length of the muzzle brake?

12" barrel...from the chamber to the end of those threads.

by J, Verified Owner, June 5, 2025
Does the 12" barrel Upper require an NFA Tax Stamp if you mount it on a standard AR15 Lower?

If you have a standard buffer tube and standard buttstock attached to that standard AR lower...then yes, of course...that's a silly question.

by J, Verified Owner, June 5, 2025
View All Q&A You Have a Question? Ask!
Customer Reviews
Helpful Positive Review
Light PDW for ambi-shooters by Southern Transplant, October 17, 2025
I purchased this out of curiosity. Ammo prices have come down to $.40/round. Hopefully, they will drop to a more reasonable $.20/round based on their actual cost to manufacture. The upper had a very stiff action at first. I disassembled it, clean...
Read More...
1/2 found this helpful
Helpful Positive Review
Great 5.7 upper. by Larry Scheller, Verified Owner, October 13, 2024
I configured mine for an AR pistol home defense build. Plenty of capacity and less over penetration than 5.56.
4/5 found this helpful
Helpful Positive Review
Really fun, low recoil, and very accurate. by Nate, May 17, 2025
I purchased my AR-57 upper quite a while back but I just took it to the range today and thought I might as well review it. First off, the thing is just downright fun. 5.7 is a little more expensive per round but it's a pleasure shoot. I shot mine as ...
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3/3 found this helpful
Helpful Negative Review
Not good, cant get muzzle device off by Chronolord, Verified Owner, September 4, 2024
I was excited for this, neat concept but is just ok and the muzzle device will not come off(wanted to try it supressed)
4/13 found this helpful
Most Recent Reviews
No magazine! by B, Verified Owner, January 7, 2024
This is the second one of these uppers I have ordered. The first one was from Aim Surplus when they first came back in stock in July of 2023. That one shipped with a 50 round mag. I enjoyed it so much that I ended up ordering a second one through Opt...
Read More...
9/33 found this helpful
Most Recent Reviews
Only negative is no magazine by Juan, December 28, 2023
Great product haven't tried it out. Down side doesn't ship with magazine. This company very anti high capacity magazines. Should have been shipped with at least a 10 round magazine. Now have to wait till i order the 50 round magazine. The magazi...
Read More...
6/20 found this helpful
Read All 8 Reviews
Caliber:
5.7x28mm
Overall Length:
24.5 in
Barrel Length:
12 in
Barrel Twist Rate:
1-8.5
Threads per Inch:
1/2x28
Muzzle Device:
Muzzle Brake
Finish:
Melonite
Color:
Black
Included Accessories:
Standard
Condition:
New

Code: 5FC-URC-AR58-AR57ULT-12

MPN: AR57ULT-12

UPC: 051497388553

List: $799.99Save 13%
$699.99

Product Info for AR57 ULT 12in Barrel 5.7x28mm Upper Receiver Assembly

DISCLAIMER: MAGAZINE IS NOT INCLUDEDimage

Specifications for AR57 ULT 12in Barrel 5.7x28mm Upper Receiver Assembly:

Manufacturer: AR57
Caliber: 5.7x28mm
Overall Length: 24.5 in
Barrel Length: 12 in
Barrel Twist Rate: 1-8.5
Threads per Inch: 1/2x28
Muzzle Device: Muzzle Brake
Finish: Melonite
Color: Black
Fabric/Material: 7075-T6 Aircraft Grade Aluminum, 8620 Alloy Steel
Gun Type: Rifle, Automatic Rifle
Gun Make: AR Platform
Included Accessories: Standard
Condition: New
Magazine Included: No
Rifling Profile: 6 Groove Rifling
Mount Type: Picatinny
Attachment Type: Picatinny

Package Contents:

  • AR57 ULT 12in Barrel 5.7x28mm Upper Receiver Assembly

AR57 ULT 12in Barrel 5.7x28mm Upper Receiver Assembly Orderable Models

List of Orderable Models

  • AR57 ULT Upper Receiver Assembly, 12in Barrel, 5.7x28mm Caliber, AR57ULT-12 , MPN: AR57ULT-12 , UPC: 051497388553 , Code: 5FC-URC-AR58-AR57ULT-12

AR57 ULT 12in Barrel 5.7x28mm Upper Receiver Assembly Unavailable & Discontinued Models

List of Unorderable Models

  • DEMO, AR57 ULT Upper Receiver Assembly, 12in Barrel, 5.7x28mm Caliber, AR57ULT-12 , MPN: AR57ULT-12-DEMO , Code: 5FC-URC-AR58-AR57ULT-12-DEMO
  • USED AR57 ULT Upper Receiver Assembly, 12in Barrel, 5.7x28mm Caliber, AR57ULT-12, EDEMO1, Used, Condition Like New , MPN: AR57ULT-12-EDEMO1 , Code: 5FC-URC-AR58-AR57ULT-12-EDEMO1
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