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Questions & Answers
Customer Reviews
Most Recent Reviews
Armalite Receiver by Fepowered, Verified Owner, January 24, 2025
This upper is in excellent condition and was a bargain. It was a new take-off but it looked new. I would purchase more of these if they become available
Most Recent Reviews
AR-10 A4 B-Series FlattopUpper by Fungun, Verified Owner, March 25, 2023
Just want to say the ArmaLite 308 upper that I received was fully assembled and ready for mounting a barrel of choice. Fit, finish and color was a perfect match to my ArmaLite lower. Installed a mid length 20” ArmaLite barrel with a flat top front si...
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Read All 2 Reviews

Product Discontinued by Manufacturer

ArmaLite AR-10 A4 B-Series Upper Receiver Assembly 7.62x51mm/.308 Winchester 10002001 has been discontinued by ArmaLite and is no longer available. Our product experts have helped us select these available replacements below.You can also explore other items in the Gun Parts, AR 15 Parts, Rifle Parts, AR15 Upper Receivers yourself to try and find the perfect replacement for you!

ATTENTION! We currently do not ship this product to P.O. Boxes, AK, CA, CT, DE, HI, MA, NJ, NY, U.S. Territories, or select Colorado locations. Please see our policies for more information or a detailed list of locations.

Product Info for ArmaLite AR-10 A4 B-Series Upper Receiver Assembly 7.62x51mm/.308 Winchester 10002001

AR-10A4 B-Series flat-top upper receiver made from forged 7075-T6 aluminum. Features a flat-top with MIL-STD 1913 rail. Thread size 1-7/16x18 UNEF-3A.image

AR-10A4 complete upper is our standard flat top upper with the standard port door rod used for all AR-10 that will utilize a 2-piece handguard. If a free float handguard is to be used, the 10002000 AR-10(T) complete upper is needed.

Package Contents:

  • ArmaLite AR-10 A4 B-Series Upper Receiver Assembly 7.62x51mm/.308 Winchester 10002001
  • AR-10 Port Door Assembly
  • AR-10 AR-10 Port Door Rod
  • AR-10 / M-15 Port Door Spring
  • AR-10 Forward Assist Kit

AR Upper Receiver Parts

160 / 60
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Ammunition

134 / 34
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Ammo Boxes

116 / 16
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Related Products to ArmaLite AR-10 A4 B-Series Upper Receiver Assembly 7.62x51mm/.308 Winchester 10002001

ArmaLite AR-10 A4 B-Series Upper Receiver Assembly 7.62x51mm/.308 Winchester 10002001 Unavailable & Discontinued Models

List of Unorderable Models

  • USED ArmaLite AR-10 A4 B-Series Upper Receiver Assembly 7.62x51mm/.308 Winchester, Black, 10002001, EDEMO1, Used, Condition Fair , MPN: 10002001-EDEMO1 , Code: A87-UPR-10002001-10002001-EDEMO1
  • ArmaLite AR-10 A4 B-Series Upper Receiver Assembly 7.62x51mm/.308 Winchester, Black, 10002001 , MPN: 10002001 , UPC: 651984091654 , Code: A87-UPR-10002001-10002001
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