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Rock River Arms A4 9MM Luger Completed Upper Up to $50.01 Off w/ Free Shipping — 4 models

Rock River Arms Completed Upper Receiver, A4 9MM Luger, 7 Inch Barrel, 1-10 Twist, 1/2-36 Thread, Free-Float Handguard, A2 Flash Hider, Black, 9MM0365B
Rock River Arms Completed Upper Receiver, A4 9MM Luger, 10.5 Inch Barrel, 1-10 Twist, 1/2-36 Thread, R4 Handguard, A2 Flash Hider, Black, 9MM0364B
Rock River Arms Completed Upper Receiver, A4 9MM Luger, 4.5 Inch Barrel, 1-10 Twist, 1/2-36 Thread, Free-Float Handguard, Vortex Flash Hider, Black, 9MM0368
Rock River Arms Completed Upper Receiver, A4 9MM Luger, 16 Inch Barrel, 1-10 Twist, 1/2-36 Thread, Free-Float Handguard, Brake, Black, 9MM0700.V1
Rock River Arms Completed Upper Receiver, A4 9MM Luger, 7 Inch Barrel, 1-10 Twist, 1/2-36 Thread, Free-Float Handguard, A2 Flash Hider, Black, 9MM0365B
1 of 4 images
Rock River Arms Completed Upper Receiver, A4 9MM Luger, 7 Inch Barrel, 1-10 Twist, 1/2-36 Thread, Free-Float Handguard, A2 Flash Hider, Black, 9MM0365B
Rock River Arms Completed Upper Receiver, A4 9MM Luger, 10.5 Inch Barrel, 1-10 Twist, 1/2-36 Thread, R4 Handguard, A2 Flash Hider, Black, 9MM0364B
2 of 4 images
Rock River Arms Completed Upper Receiver, A4 9MM Luger, 10.5 Inch Barrel, 1-10 Twist, 1/2-36 Thread, R4 Handguard, A2 Flash Hider, Black, 9MM0364B
Rock River Arms Completed Upper Receiver, A4 9MM Luger, 4.5 Inch Barrel, 1-10 Twist, 1/2-36 Thread, Free-Float Handguard, Vortex Flash Hider, Black, 9MM0368
3 of 4 images
Rock River Arms Completed Upper Receiver, A4 9MM Luger, 4.5 Inch Barrel, 1-10 Twist, 1/2-36 Thread, Free-Float Handguard, Vortex Flash Hider, Black, 9MM0368
Rock River Arms Completed Upper Receiver, A4 9MM Luger, 16 Inch Barrel, 1-10 Twist, 1/2-36 Thread, Free-Float Handguard, Brake, Black, 9MM0700.V1
4 of 4 images
Rock River Arms Completed Upper Receiver, A4 9MM Luger, 16 Inch Barrel, 1-10 Twist, 1/2-36 Thread, Free-Float Handguard, Brake, Black, 9MM0700.V1

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Questions & Answers
Does this BCG work with Glock magazines?

Yes, this is the complete upper that RRA sells with their BT9G lower, the lower made for Glock mags.

by davidd, Verified Owner, October 16, 2025
View All Q&A You Have a Question? Ask!
Customer Reviews
Most Recent Reviews
LivingstonMT by Nicholas, Verified Owner, December 7, 2025
Great product. Packaging and protection of product excellent. Parts and pieces excellent condition. Easy assembly. After assembly, shoots very nice.
Read 1 Review
4 Models Available
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Product Info for Rock River Arms A4 9MM Luger Completed Upper

The Rock River Arms A4 9MM Luger Completed Upper was developed in order to function as the best item for anybody needing a high quality selection..image

Formulated working with several of the very most robust and dependable materials available, these AR15 Upper Receivers from Rock River Arms can provide a product that will give many years of dependability.

Rock River Arms has been making high-quality merchandise for a number of years, and the Rock River Arms A4 9MM Luger Completed Upper is their very own manner of showing you exactly how much they are concerned.

Here at OpticsPlanet, we make it our responsibility to get the perfect product for all your preferences, and exhibiting the Rock River Arms A4 9MM Luger Completed Upper is something that we are pleased to offer.

WARNING: California`s Proposition 65

Specifications for Rock River Arms A4 9MM Luger Completed Upper:

Manufacturer: Rock River Arms
Caliber: 9mm Luger
Barrel Twist Rate: 1-10
Threads per Inch: 1/2x36
Handguard Type: R4
Finish: Anadized
Color: Black
Fabric/Material: Aluminum
Barrel Material: Chrome Moly
Bolt Carrier Group Included: COM-SPEC
Magazine Included: No

Package Contents:

  • Rock River Arms A4 9MM Luger Completed Upper
  • Bolt Carrier Group
  • Charging Handle Assembly

Rock River Arms A4 9MM Luger Completed Upper Orderable Models

List of Orderable Models

  • Rock River Arms Completed Upper Receiver, A4 9MM Luger, 7 Inch Barrel, 1-10 Twist, 1/2-36 Thread, Free-Float Handguard, A2 Flash Hider, Black, 9MM0365B , MPN: 9MM0365B , UPC: 842834103942 , Code: 1WN-URC-AN49-9MM0365B
  • Rock River Arms Completed Upper Receiver, A4 9MM Luger, 10.5 Inch Barrel, 1-10 Twist, 1/2-36 Thread, R4 Handguard, A2 Flash Hider, Black, 9MM0364B , MPN: 9MM0364B , UPC: 842834103935 , Code: 1WN-URC-AN49-9MM0364B
  • Rock River Arms Completed Upper Receiver, A4 9MM Luger, 4.5 Inch Barrel, 1-10 Twist, 1/2-36 Thread, Free-Float Handguard, Vortex Flash Hider, Black, 9MM0368 , MPN: 9MM0368 , UPC: 842834124947 , Code: 1WN-URC-AN49-9MM0368
  • Rock River Arms Completed Upper Receiver, A4 9MM Luger, 16 Inch Barrel, 1-10 Twist, 1/2-36 Thread, Free-Float Handguard, Brake, Black, 9MM0700.V1 , MPN: 9MM0700.V1 , UPC: 842834101122 , Code: 1WN-URC-AN49-9MM0700-V1
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