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FN America FN15 20 Inch Rifle Upper Assembly 36427

FN America 20 Inch Rifle Upper Assembly
FN America 20 Inch Rifle Upper Assembly
FN America 20 Inch Rifle Upper Assembly
FN America 20 Inch Rifle Upper Assembly
FN America 20 Inch Rifle Upper Assembly
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FN America 20 Inch Rifle Upper Assembly
FN America 20 Inch Rifle Upper Assembly
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FN America 20 Inch Rifle Upper Assembly
FN America 20 Inch Rifle Upper Assembly
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FN America 20 Inch Rifle Upper Assembly
FN America 20 Inch Rifle Upper Assembly
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FN America 20 Inch Rifle Upper Assembly

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Questions & Answers
will this upper work with my fn 1776 lower and do I need any other parts Expert Answer

Yes it should fit as the FN 15 1776 uses a mil-spec lower receiver. It is a complete upper, and should be ready for use out of the box.

by Jonathan D., Gear Expert, May 18, 2018
See 1 More Answer
I live in CA and cannot have a flash hider. If I purchase this upper along with a compensator from you can you install it for me? Expert Answer

Unfortunately, we do not offer installation services at this time.

by Carly R., Gear Expert, May 24, 2018
View All Q&A You Have a Question? Ask!
Customer Reviews
Helpful Positive Review
fn upper review by CHRIS URSINY, June 15, 2019
my cousin has this product, felt recoil is low and good, accuracy is excellent when using a variety of different bullet types and the upper does not get as hot as a carbine or mid-length gas system, so generally speaking accuracy is great, felt r...
Read More...
2/2 found this helpful
Helpful Positive Review
Mil spec greatness by Expert Marksman, July 26, 2017
This is the real deal! Mil spec, accurate, and chrome lined. This is a top tier upper for a great price. Buy one while you can. I have had zero malfunctions, 9 rounds to sight in. Build a FN 20in AR and relive your basic training days. Better than m...
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5/7 found this helpful
Helpful Positive Review
A quick and easy upgrade. by FireAdjuster, July 11, 2016
The FN upper assembly allowed me to quickly and easily upgrade my older Post-Ban Colt AR-15 to more current specifications. The FN upper assembly incorporates most all of the improvements that have been made to the AR-15A2 platform in an easily insta...
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3/4 found this helpful
Most Recent Reviews
fn upper review by CHRIS URSINY, June 15, 2019
my cousin has this product, felt recoil is low and good, accuracy is excellent when using a variety of different bullet types and the upper does not get as hot as a carbine or mid-length gas system, so generally speaking accuracy is great, felt r...
Read More...
Read All 4 Reviews

Product Discontinued by Manufacturer

FN America FN15 20 Inch Rifle Upper Assembly 36427 has been discontinued by FN America and is no longer available. Our product experts have helped us select these available replacements below.You can also explore other items in the Gun Parts, AR 15 Parts, Rifle Parts, AR15 Upper Receivers yourself to try and find the perfect replacement for you!

ATTENTION! We currently do not ship this product to P.O. Boxes, AK, CA, CT, DE, HI, MA, NJ, NY, U.S. Territories, or select Colorado locations. Please see our policies for more information or a detailed list of locations.

Product Info for FN America FN15 20 Inch Rifle Upper Assembly 36427

Complete upper assembly includes, bolt carrier group and charging handle. Barrel cold hammer forged. Proprietary CrMoV barrel steel. Hard-chrome lines to mil-std 171. M4 feed ramps. High pressure tested. Magnetic particle inspected. Manganese phosphate finish. Chambered in 5.56x45mm. 1:7 RH twist. Bolt carrier group/ bolt. M16 auto bold carrier assembly. Carpenter 158 bolt ( magnetic particle inspected). Staked gas key.image

Specifications for FNH USA FN15 20 Inch Rifle Upper Assembly 36427:

Mfg Item Num:  36427
Type:  ACCESSORIES - GUN ACCESSORIES - UPPER RECEIVERS
Barrel Length:  20
Model Header:  20 Inch Rifle Upper
Master Model Header:  Upper Assembles

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FN America FN15 20 Inch Rifle Upper Assembly 36427 Unavailable & Discontinued Models

List of Unorderable Models

  • FN America 20 Inch Rifle Upper Assembly , MPN: 36427 , UPC: 845737005986 , Code: 57D-UFH-36427
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Last updated 2026-08-18 UTC.