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FN America Ar15 Barrel, 20inch Bb M16 5.56 Rifle

FN America Ar15 Barrel, 20 Bb M16 5.56 Rifle - 20-100043
FN America Ar15 Barrel, 20 Bb M16 5.56 Rifle - 20-100043
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FN America Ar15 Barrel, 20 Bb M16 5.56 Rifle - 20-100043

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Questions & Answers
what length gas tube will I need? thanks

A rifle length gas tube. Look it up, pup.

by Lord B., Verified Owner, January 7, 2022
See 1 More Answer
Are these barrels cold hammer forged?

No, button rifling

by Pickle Rick, Verified Owner, December 1, 2024
View All Q&A You Have a Question? Ask!

Code: 57D-ATB-FNH-20-100043-EE

MPN: 20-100043

UPC: 845737008550

Product No Longer Available

Product Info for FN America Ar15 Barrel, 20inch Bb M16 5.56 Rifle

The Bore And Chamber Are Chrome Lined To Help Resist Corrosion And Provide Resistance To Heat Erosion Which Greatly Improves Barrel Life And Reliable Chambering / Extraction. The M4 Style Feed Ramps And Barrel Extension Provide Consistent Feeding And The Matte Black Manganese Phosphate Finish Resists External Corrosion And Oxidation.image

Package Contents:

  • FN America Ar15 Barrel, 20inch Bb M16 5.56 Rifle

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FN America Ar15 Barrel, 20inch Bb M16 5.56 Rifle Unavailable & Discontinued Models

List of Unorderable Models

  • FN America Ar-15 Button Rifled Barrel Oal M16 - 20-100043 , MPN: 20-100043 , UPC: 845737008550 , Code: 57D-ATB-FNH-20-100043-EE
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Last updated 2026-08-18 UTC.