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Questions & Answers
Will this work on the Radio delay blowback 9 mm CMMG barrel s Expert Answer

Yes, this upper would work with that barrel and bcg.

by Kurt Colbourne, Gear Expert, October 7, 2021
Will this fit on a AR15 lower Expert Answer

Yes, it will.

by Kurt Colbourne, Gear Expert, October 7, 2021
Customer Reviews
Helpful Positive Review
Quality product by Ranger40, January 26, 2017
This is a quality product that you would expect to get from a company like cmmg. The machining is flawless inside and out. The finish is also vey even and smoothe and a very nice deep shade of black. I don't think you will be dissapointed this upper.
1/1 found this helpful
Helpful Positive Review
My upper receiver by Meg, July 11, 2020
I love it! But I was hoping they’d send me a sticker. I didn’t get a sticker. Other than that I love it. It took awhile to ship, which was understandable given the events in 2020. I will definitely continue purchasing from Optics Planet.
1/1 found this helpful
Most Recent Reviews
Great choice for a build by Biggs, Verified Owner, May 11, 2017
I ordered this and paired it to a PSA lower. The fit was great. The finish is a little more matte than the lower but only on really close inspection. No play between the upper and lower. Everything fit together well. I am very pleased with it and wou...
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Read All 3 Reviews
Color: Black Finish: Anodized Fabric/Material: Billet 7075 T6 AL Gun Model: M4 Condition: New

Code: 2CM-UPR-CMMG55BA142-EE

MPN: 55BA142

UPC: 852005002561

Product No Longer Available

Product Info for CMMG, Inc M4 Forged Mil-Spec Upper Receiver

Stripped AR15 upper receiver. Dust cover and forward assist assembly not included.image

Features of CMMG, Inc M4 Forged Mil-spec Upper Recei:

  • Forged 7075 T6 AL
  • Incredibly reliable
  • Long lasting

Package Contents:

  • CMMG, Inc M4 Forged Mil-spec Upper Recei

5.56x45mm NATO Ammo

1–10 / 10
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AR Upper Receiver Parts

1–27 / 27
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Gun Sights

1–12 / 12

Gun Parts and Accessories

1–28 / 28
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Magazine and Accessories

1–25 / 25
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Gun Barrels

1–12 / 12
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Gun Stocks

1–16 / 16
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CMMG, Inc M4 Forged Mil-Spec Upper Receiver Unavailable & Discontinued Models

List of Unorderable Models

  • CMMG, Inc Upper Receiver, MK4, 55BA142 , MPN: 55BA142 , UPC: 852005002561 , Code: 2CM-UPR-CMMG55BA142-EE
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