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Home Rifle Parts Receiver Parts Receivers Upper Receivers ROCK RIVER ARMS A4 9MM UPPER RECEIVER Support
Convert your AR to 9mm with the A4 Upper Receiver! 🔧 Durable, complete assembly with military specs for optimal performance.

ROCK RIVER ARMS A4 9MM UPPER RECEIVER - ROCK RIVER ARMS A4 9MM UPPER RECEIVER

739000013

Restrictions

  • Is a 'Call to order' product.

Top takeaways

  1. The Rock River Arms A4 9mm Upper Receiver allows easy conversion of ARs chambered in .223 to 9mm Luger.
  2. It is a complete upper receiver with military specification components, including a Wilson 1-10 twist barrel and a flattop receiver for Picatinny rail accessories.
  3. Conversion to 9mm also requires a 9mm magazine, magazine adapter, action spring, and recoil buffer, which are not included.

Attributes

  • Cartridge: 9 mm Luger
  • Colour: Black
  • Finish: Anodized
  • Make: AR-15
  • Twist: 1-10
  • Delivery weight: 1.86kg
  • Shipping height: 114mm
  • Shipping width: 114mm
  • Shipping length: 635mm

Item details

Made in USA
US export classification: I(g)
  • Specifications:
  • Cartridge: 9 mm Luger
  • Color: Black
  • Finish: Anodized
  • Make: AR-15
  • Twist: 1-10
739.9 739.9 1 GBP
739.9 GBP 0 £739.90

Prices inclusive of duty & VAT.

Product no.: 739000013

Mfr. No.: 9MM0350B

Sub-caliber upper assemblies allow fast and simple conversion of ARs chambered in .223 to 9mm Luger. True, dedicated, complete upper receivers are assembled from military specification components; includes a Wilson, 1-10 twist barrel, bolt and carrier, charging handle, shell deflector, heat-shield lined handguards, sling swivel, and A1-style flash hider. Additional items not included but required for conversion to 9mm are a 9mm magazine (739-000-014); magazine adapter, action spring, and recoil buffer (080-000-442). A4 unit has flattop receiver that accepts most aftermarket accessories designed to fit a Picatinny rail.
Not available - Is a 'Call to order' product.
2

Not available.

Is a 'Call to order' product.

Not available.

Wish List Ask question
Requires order by phone
  • Specifications:
  • Cartridge: 9 mm Luger
  • Color: Black
  • Finish: Anodized
  • Make: AR-15
  • Twist: 1-10

Description:

Sub-caliber upper assemblies allow fast and simple conversion of ARs chambered in .223 to 9mm Luger. True, dedicated, complete upper receivers are assembled from military specification components; includes a Wilson, 1-10 twist barrel, bolt and carrier, charging handle, shell deflector, heat-shield lined handguards, sling swivel, and A1-style flash hider. Additional items not included but required for conversion to 9mm are a 9mm magazine (739-000-014); magazine adapter, action spring, and recoil buffer (080-000-442). A4 unit has flattop receiver that accepts most aftermarket accessories designed to fit a Picatinny rail.

Restrictions

  • Is a 'Call to order' product.

Top takeaways

  1. The Rock River Arms A4 9mm Upper Receiver allows easy conversion of ARs chambered in .223 to 9mm Luger.
  2. It is a complete upper receiver with military specification components, including a Wilson 1-10 twist barrel and a flattop receiver for Picatinny rail accessories.
  3. Conversion to 9mm also requires a 9mm magazine, magazine adapter, action spring, and recoil buffer, which are not included.

Attributes

  • Cartridge: 9 mm Luger
  • Colour: Black
  • Finish: Anodized
  • Make: AR-15
  • Twist: 1-10
  • Delivery weight: 1.86kg
  • Shipping height: 114mm
  • Shipping width: 114mm
  • Shipping length: 635mm

Item details

Made in USA
US export classification: I(g)

Customers reviews

Customer ratings (2)

5 / 5
Definitely recommended

Brownells USA Flawless 28/11/2010

I've been using this upper for two years. It's well finished. On the outside, the finish is as good as ever, and there's no wear beyond the ordinary inside and on the bolt. The carrier staking is well done and there's no looseness anywhere.

It works flawlessly on a Bushmaster lower equipped with a Hahn Precision dedicated magazine block, Spike's Tactical extended 9x buffer, and Metalform magazines. I use it more than my other AR-15s--low cost ammo and a lot of fun. My wife and son enjoy shooting it as well.

Definitely recommended

Brownells USA 9mm Carbine 23/09/2009

I really like this upper receiver. I built this upper on a Rock River lower with a dedicated 9mm conversion block and have been very pleased with its performance.

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