CMMG 5.7 8" Quad AR15 PDW Pistol Upper Group CQB Mk57 5.7x28mm AR-15 AR57 Phase 5

CMMG 5.7 8" Quad AR15 PDW Pistol Upper Group CQB Mk57 5.7x28mm AR-15 AR57 Phase 5

Add the ultimate all-in-one caliber (handgun, PDW, rifle) with this Lightweight Complete Upper Receiver built around the reliable CMMG 5.7x28mm Radial Delayed Blowback System to any existing AR15 lower! Built around the M4E1 Aero Precision Forged Upper Receiver and using the sleek Phase 5 Quad Rail, this package has it all: Power, Functionality, and Great Looks. We recommend the Guntec sleeved Muzzle Brake but and assortment of muzzle options are available. Don't see the one you want, just ask!

Ultralight and compact while bringing higher capacity and power, this 5.7 Upper Group is a fantastic Close Quarters CQB Personal Defensive Weapon PDW choice for your next Short Barreled Rifles (SBR’s- All NFA Rules Apply) or AR pistol build. 

Optional Muzzle Device Choices:

A2 Flash Hider

VG6 Gamma Brake

Strike Industries Cloak Hider

Hera LCS Linear Compensator Small

Tiger Fake Suppressor (3" Barrel Sleeve)

BLACK Guntec USA Muzzle Brake (6" Barrel Sleeve)

RED Guntec USA Muzzle Brake (6" Barrel Sleeve)

Includes:

• Aero M4E1 AR15 Assembled Upper Receiver with No Forward Assist

• Phase 5 Quad Rail Angled Handguard

• Aero Breach Ambidextrous Charging Handle INCLUDED

• CMMG 8” 1:9 Twist, Medium Taper 4140 SBN

• CMMG 5.7 BCG INCLUDED

• Product comes assembled with CMMG's Lifetime Quality Guarantee

• The muzzle device that comes with this complete upper receiver must be selected and is NOT pinned nor welded to this barrel. NO MAGAZINE INCLUDED UNLESS ADDED.

Aero M4E1 AR15 Upper Receiver with No Forward Assist Features:

• M4 Feedramps

• Forged 7075-T6 Aluminum

• .250 takedown pin holes

• Laser engraved T-marks

• No forward assist provisions

• Port door installed

Phase 5 LPSN Quad Handguard Features:

• Full top picatinny rail for optional attachments

• Quick disconnect sling socket at the 3, 6 and 9 o'clock positions

• 1.3" Inside diameter

• 1.5" Outside diameter

8" 5.7mm Pistol Length Barrel Features:

• Chamber: 5.7mm

• Length: 8"

• Twist: 1 in 9

• Threading: 1/2"x28

• Material: Chrome Moly Vanadium

• Finish: QPQ corrosion resistant finish both inside and out

• Gas System: Delayed Blowback

• Weight: 17.25 oz

• M4 Barrel Extension

Specs:

Optional ADD-ON:

32 Round Mag

CMMG’s 5.7 AR Conversion Magazine holds 32 rounds of 5.7x28mm and fits in any standard AR15 lower receiver. To use, simply attach a CMMG 5.7x28mm Radial Delayed Blowback complete upper receiver to an existing AR15 lower. Then, insert CMMG’s 5.7 AR Conversion Magazine to safely feed 5.7x28mm ammunition. CMMG recommends using a standard carbine buffer and action spring to reliably cycle the action in this configuration. The 5.7 AR Conversion Magazine also retains last round bolt hold-open functionality, allowing for faster reloads.

CALIBER: 5.7x28mm

CAPACITY: 32 rounds

WEIGHT: 8oz(unloaded)