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Rifle Parts Receiver Parts Receivers Upper Receivers ROCK RIVER ARMS A4 9MM UPPER RECEIVER Support

Convert your .223 AR to 9mm Luger easily with the Rock River Arms A4 9MM Upper Receiver, featuring military-grade components and a versatile flattop design.

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
  • Twist: 
    1-10
  • Weapon type: 
    AR-15
  • 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 £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
5/5 - 2 Customers

Not available.

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739.9 739.9 1 GBP
Description Specification Customers reviews Accessories

ROCK RIVER ARMS A4 9MM UPPER RECEIVER

739.9 GBP £739.90

Prices inclusive of duty & VAT.

Is a 'Call to order' product.
Requires order by phone

Description:

Transform your AR with the A4 9MM Upper Receiver

The A4 9MM Upper Receiver from Rock River Arms is designed for those looking to convert their ARs chambered in .223 to 9mm Luger quickly and efficiently. This dedicated upper assembly is crafted from military specification components, ensuring reliability and performance.

Key Features:

  • Barrel: 4140 steel, blue, matte finish, 16” (40.6cm) long, .725” (18cm) O.D.
  • Receiver: Aluminum, anodized finish, matte black.
  • Flattop receiver accepts most aftermarket accessories designed to fit a Picatinny rail.
  • 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.

Conversion Requirements:

To complete the conversion to 9mm, additional items are necessary:

  • 9mm magazine (739-000-014)
  • Magazine adapter
  • Action spring
  • Recoil buffer (080-000-442)

Designed to fit lower receivers with .25” (6.3mm) diameter takedown pins, the A4 unit provides a seamless upgrade for your firearm.



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
  • Twist: 
    1-10
  • Weapon type: 
    AR-15
  • 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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