Radical Firearms .458 SOCOM AR-15 Upper Receiver Assembly - Forward Assist and Dust cover Assembly

Manufactured by Radical Firearms
SKU: FU-458-C
MPN: FU-458-C
Manufactured by Radical Firearms
2 Reviews

In Stock

Standard orders will ship out 1 business day if ordered by 3:30 pm CST, Monday-Friday. FFL orders will ship within 5 business days or less as long as we have the information for the transfer destination.

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Start your next big bore AR-15 build off right with a quality forged upper receiver specially designed with the big calibers in mind. The Radical firearms .458 SOCOM upper receiver assembly is a great option whether you want to build a big bore carbine or a completely custom AR-15 rifle. This Upper is forged from durable 7075 aircraft grade aluminum that is stronger than other materials commonly used in AR-15 receivers. It also has a tough type 3 hardcoat anodized finish that provides excellent wear and corrosion resistance, so you can count on this receiver lasting a long time. The picatinny top rail is great for mounting scopes or red dot sights depending on how you want to set up your rifle. This big bore upper is even fully assembled with forward assist and port door.

  • Expanded ejection port for large calibers
  • Mil-Spec flat top upper receiver
  • Compatible with Mil-Spec lower receivers
  • Forged from 7075 aircraft grade aluminum
  • Type 3 hardcoat anodized finish
  • Picatinny top rail
  • Machined shell deflector and forward assist slot

Radical Firearms offers law enforcement grade hardware. Crafted with quality materials and covered by their lifetime warranty, Radical Firearms is an outstanding choice for any budget.
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AssemblyAssembled Uppers
BrandRadical Firearms
Forward AssistAssembled with Forward Assist
Port DoorAssembled with Port Cover
T MarksUnmarked

Ratings & Reviews

2 reviews

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Nice Value Upper


Fit and finish is great and I can confirm that this will work with a 450 Bushmaster barrel in case anyone is wondering.

WOW Quality at a "great" price!!!

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I received my daily/weekly alerts from Primary Arms and i cant say enough about ,both the quality and prices of all the products they carry at even its regular prices! But boy did i luck out! The total of my bills with shipping "if" it wasnt free shipping was $69.99!!! I ordered it June 26th and it arrived at my house today! ">) Man thats fast i didnt pay for any out of the ordinary shipping and would have to go back into my bill to see if there was even a shipping charge? It was one of their flash sales or was it a secret sale?rofl either way top quality i just love RF and have been wanting to build a 458Socom for some time! All my rifles have dedicated lowers ,none of that 5uppers with one lower! for me! I want one in every caliber an AR comes in! then ill start on AR10s if im still young enough! HAHA Quality and a "Great" price!!! Dont you go changing Primary Arms you guys are almost perfect! Almost.....dont go getting a swelled head! hehehe