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Q&A for Radical Firearms 7.5 in. 5.56 M4 Upper Assembly — 7 Questions & 7 Answers

Name Radical Firearms 7.5 in. 5.56 M4 Upper Assembly (5)
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Q
Phil, guest, from CA, United States, asked on November 30, 2022

Will this fit mp15 sport two lower

Expert Answer
A
Answered by Ethan, Gear Expert, from IL, United States, on December 01, 2022

Yes, the Radical Firearms 7.5 in. 5.56 M4 Upper Assembly will fit and function as intended on your M&P-15 Sport II lower receiver.

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Q
Carl Stacey, member, from NC, United States, asked on June 03, 2022

Will this fit the G150 Phoenix AR-15 80% Lower ?

Expert Answer
A
Answered by Ethan, Gear Expert, from IL, United States, on June 10, 2022

The Radical Firearms 7.5 in. 5.56 M4 Upper Assembly is designed to fit Mil-spec AR15 lower receivers. There is no guarantee it will fit an 80% lower due to variations between different 80% builds.

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Q
Mikkeeyy Mikkee, guest, from MI, United States, asked on February 24, 2022

Will this fit the rf-15 model?

Expert Answer
A
Answered by Hunter, Gear Expert, from OH, United States, on March 09, 2022

Yes, the Radical Firearms 7.5 in. 5.56 M4 Upper Assembly will fit the RF15 Lower Receiver.

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Q
Donky, member, from NV, United States, asked on February 16, 2022

Is the barrel 1/2x28 on the .223/5.56 model?

Expert Answer
A
Answered by Hunter, Gear Expert, from OH, United States, on February 22, 2022

Yes, the Radical Firearms 7.5 in. 5.56 M4 Upper Assembly barrel is threaded for 1/2x28.

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Q
Pete, member, from MN, United States, asked on February 14, 2021

What is the inside diameter of the handguard?

Expert Answer
A
Answered by Nick B., Gear Expert, from IL, United States, on October 25, 2021

The inner diameter is 1.8".

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Q
DAVID, member, from NC, United States, asked on February 04, 2021

I WOULD LIKE TO KNOW IF YOUR ABLE TO SHOOT 223 AMMO WITH THIS UPPER ASSEMBLY

Expert Answer
A
Answered by Nick B., Gear Expert, from IL, United States, on October 25, 2021

Yes, these uppers will be able to fire both .223 Remington and 5.56 NATO.

1 of 1 found the following answer helpful.
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Q
Kc, guest, from LA, United States, asked on September 06, 2020

The product info sais "with BCG", the description sais BCG is additional. Which is correct?

A
Answered by Stump, member, from IN, United States, on June 23, 2021

you aren't spelling "says" correct. Hence no one answering to you saying "sais" . I think you asking for a "BCG" is minor to your edgamacation and grammar issues.

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Last updated 2025-11-12 UTC.