Free shipping on orders over $500Free shipping over $500 • Fast processing • Family owned • ★ A+ rated on GunBroker (2,965 ratings)★ A+ on GunBroker Help Order status info@nautilusarms.com

Uppers & Conversion Kits

Uppers & Conversion Kits from Radian Weapons, CMMG, Advantage Arms and more, with in-stock items listed first.

Tacfire Inc.

Tacfire Complete Upper with BCG 9mm Luger 10" Black - BU-9MM-10

✕ Out of stock

MSRP:

Was:

Now: $300.60
Chiappa

Chiappa X-Caliber 20 Gauge/410/ 45LC Gauge Adapter Insert. - CF710403

✕ Out of stock

MSRP:

Was:

Now: $61.10
Anderson Manufacturing

Anderson Upper Receiver Sub-Assy.AM-15W/Standard Charging HandleBlk [Retail Pkg) - B2-K601-A000-0P

✕ Out of stock

MSRP:

Was:

Now: $111.34
Yankee Hill Machine

Yankee Hill Machine Stripped Billet Upper Receiver For AR-15 - YHM110BILLET

✕ Out of stock

MSRP: $229.95

Was:

Now: $173.95
Colt's Manufacturing

Colt's M4 Upper Black - SP63528

✕ Out of stock

MSRP: $179.99

Was:

Now: $152.05
Faxon Firearms

Faxon ARAK-21 Complete Upper Receiver 5.56 NATO 12.5" Barrel - URSSB556P

✕ Out of stock

MSRP: $999.00

Was:

Now: $858.25
Franklin Armory

Franklin Armory F17 L 20" Upper Kit 17 WSM 10rd Magazine, Black - 0040073BLK

✕ Out of stock

MSRP: $1,189.99

Was:

Now: $989.73
Barrett Firearms

Barrett MRAD Conversion Kit .300 Norma Magnum Fluted Barrel 26" Black - 19421

✕ Out of stock

MSRP: $1,760.00

Was:

Now: $1,647.00
Cmmg Inc.

CMMG Upper Group Banshee 5.7x28mm 8" Black - 57B88BD-AB

✕ Out of stock

MSRP:

Was:

Now: $832.64
Tacfire Inc.

Tacfire AR-15 Complete Upper 9mm Luger 7" 1/2x36 Threaded Barrel Black - BU-9MM-7

✕ Out of stock

MSRP:

Was:

Now: $286.43
Radian Weapons

Radian Weapons Model 1 Complete AR-15 Upper 223 Wylde 10.5 FDE - R0452

✕ Out of stock

MSRP: $1,904.95

Was:

Now: $1,680.98
Heckler and Koch (HK USA)

HK Upper Kit 7.62mm 13"7.62 x 51mm 308 Win - 51001919

✕ Out of stock

MSRP: $3,049.00

Was:

Now: $2,685.00
COLT

Colt Upper Receiver Conversion Kit 5.56 16.1" - LE6940CK

✕ Out of stock

MSRP: $1,219.00

Was:

Now: $975.96
Cmmg Inc.

CMMG Banshee MK4 AR-15 Upper Group 338 ARC 10.5" Barrel Black - 34B8D0F-AB

✕ Out of stock

MSRP:

Was:

Now: $733.21
Battle Arms Development

Battle Arms Development AR-15 Lightweight Upper Receiver Billet Black - 100-016-156

✕ Out of stock

MSRP: $259.95

Was:

Now: $212.70
Tacfire Inc.

Tacfire AR-15 Complete Upper 5.56 NATO 11.5" Barrel Black - BU-556-11.5

✕ Out of stock

MSRP:

Was:

Now: $293.62
Fortis Manufacturing, Inc.

Fortis Billet Upper Receiver - U-Billet-M4

✕ Out of stock

MSRP: $199.95

Was:

Now: $175.95
Luth-AR

Luth-AR 308 Upper Receiver - 308-FTT-EA

✕ Out of stock

MSRP:

Was:

Now: $169.05
Yankee Hill Machine Co

Yankee Hill Machine A3 Upper Receiver Assembly For AR-15 - YHM-100

✕ Out of stock

MSRP: $174.95

Was:

Now: $134.11
Radian Weapons

Radian Weapons Upper/Handguard Set 17" Gray - R0611

✕ Out of stock

MSRP: $999.95

Was:

Now: $815.91
Advantage Arms

Advantage Arms CNV CA 10-Round - AAC26-27G1-5MOD-CA

✕ Out of stock

MSRP: $295.00

Was:

Now: $259.33
CMMG

CMMG 22LR AR Conv Kit Stainless 25-Round EVO

✕ Out of stock

MSRP: $199.95

Was:

Now: $173.42
Rock River Arms

Rock River Arms Cmplt Car A4 Upper 458 SOCOM 16" - SOC0564

✕ Out of stock

MSRP: $790.00

Was:

Now: $680.11
Nordic Components

Nordic Components NC15 Extruded Upper Receiver Black - NC15-UR-EXT

✕ Out of stock

MSRP: $99.95

Was:

Now: $96.39

Previous
11
12
13
14
15
16
17
18
19
Next