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XTS AR-15 8.5in 300 BO Complete Upper Receiver w/o BCG XTSCU8300BK Caliber: .300 AAC Blackout, Overall Length: 17.5 in, 22% Off w/ Free S&H

XTS Complete Upper Receiver w/o BCG, AR-15, 300 BO, 17.5in, 8.5in, Pistol Length, 1-8 Twist, 5/8x24 Thread, M-LOK Handguard, Bird Cage, Black Nitride Finish, Black, XTSCU8300BK
XTS Complete Upper Receiver w/o BCG, AR-15, 300 BO, 17.5in, 8.5in, Pistol Length, 1-8 Twist, 5/8x24 Thread, M-LOK Handguard, Bird Cage, Black Nitride Finish, Black, XTSCU8300BK
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XTS Complete Upper Receiver w/o BCG, AR-15, 300 BO, 17.5in, 8.5in, Pistol Length, 1-8 Twist, 5/8x24 Thread, M-LOK Handguard, Bird Cage, Black Nitride Finish, Black, XTSCU8300BK

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Questions & Answers
Does it come with a 556 barrel or 300bo greatly appreciate if you could fix the listing to the correct info Manufacturer Answer

300 Blackout barrel

by XTS, Manufacturer, July 23, 2025
Will this particular upper property function on a Sig MCX lower? Expert Answer

No, An MCX lower is designed for the MCX upper which doesn't use a buffer tube assembly like a typical AR15 does. So, an Ar15 upper would not function with an MCX lower.

by Ethan, Gear Expert, March 29, 2024
View All Q&A You Have a Question? Ask!
Caliber:
.300 AAC Blackout
Overall Length:
17.5 in
Barrel Length:
8.5 in
Gas System Length:
Pistol Length
Barrel Twist Rate:
1-8
Threads per Inch:
5/8x24
Muzzle Device:
A2 Flash Hider
Finish:
Nitride
Color:
Black
Gun Model:
AR-15
Condition:
New
Gas Block Journal Size-Diameter:
.750 in
Handguard Length:
7 in
Weight:
16 oz

Code: 20R-UFH-ARBOUP-XTSCU8300BK

MPN: XTSCU8300BK

UPC: 767820106687

List: $299.99Save 22%
$233.99

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OP Bucks$7.56

ATTENTION! We currently do not ship this product to AK, CA, HI, IL, NY, WA, P.O. Boxes, and U.S. Territories. Please see our policies for more information.

made-in-usa-flag Made in USA

Help support American manufacturing! Marked models of this product have gone through rigorous review and been certified by the manufacturer as Made in the USA.

Product Info for XTS AR-15 8.5in 300 BO Complete Upper Receiver w/o BCG

Our complete 8.5in AR15 300 Blackout upper comes FULLY ASSEMBLED With an Anchor Harvey Upper and an XTS Hand Guard.image

*These XTS complete uppers do not include the Bolt Carrier Group.

Specifications for XTS AR-15 8.5in 300 BO Complete Upper Receiver w/o BCG:

Manufacturer: XTS
Caliber: .300 AAC Blackout
Overall Length: 17.5 in
Barrel Length: 8.5 in
Gas System Length: Pistol Length
Barrel Twist Rate: 1-8
Threads per Inch: 5/8x24
Muzzle Device: A2 Flash Hider
Finish: Nitride
Color: Black
Gun Model: AR-15
Condition: New
Fabric/Material: Stainless Steel
Gas Block Journal Size-Diameter: .750 in
Handguard Length: 7 in
Handguard Style: Round Rail
Gun Rail: M-LOK
Gun Make: AR Platform
Barrel Material: 4150 Chrome Moly Vanadium
Bolt Carrier Group Included: No
Charging Handle Included: MIL-SPEC
Weight: 16 oz
Magazine Included: No
Mount Type: M-LOK
Country of Origin: USA

Package Contents:

  • XTS AR-15 8.5in 300 BO Complete Upper Receiver w/o BCG
  • Anachor Upper Receiver
  • 5.56 NATO Barrel 8.5in
  • XTS Charging Handle
  • XTS Forward Assist
  • XTS Ejection Port Cover
  • 7in M-LOK
  • Black Gas Block
  • Gas Tube
  • Bird Cage Muzzle Brake

What firearm models does the manufacturer say XTS AR-15 8.5in 300 BO Complete Upper Receiver w/o BCG is compatible with?

The manufacturer says that XTS AR-15 8.5in 300 BO Complete Upper Receiver w/o BCG is compatible with AR-15

XTS AR-15 8.5in 300 BO Complete Upper Receiver w/o BCG Orderable Models

List of Orderable Models

  • XTS Complete Upper Receiver w/o BCG, AR-15, 300 BO, 17.5in, 8.5in, Pistol, 1-8 Twist, 5/8x24 Thread, M-LOK, Bird Cage, Black Nitride Finish, XTSCU8300BK , MPN: XTSCU8300BK , UPC: 767820106687 , Code: 20R-UFH-ARBOUP-XTSCU8300BK

XTS AR-15 8.5in 300 BO Complete Upper Receiver w/o BCG Unavailable & Discontinued Models

List of Unorderable Models

  • USED XTS Complete Upper Receiver w/o BCG, AR-15, 300 BO, 17.5in, 8.5in, Pistol, 1-8 Twist, 5/8x24 Thread, M-LOK, Bird Cage, Blue, XTSCU8300BL, EDEMO1, Condition Parts Only/Salvage, Defective , MPN: XTSCU8300BL-EDEMO1 , Code: 20R-UFH-ARBOUP-XTSCU8300BL-EDEMO-DF-F
  • USED XTS Complete Upper Receiver w/o BCG, AR-15, 300 BO, 17.5in, 8.5in, Pistol, 1-8 Twist, 5/8x24 Thread, M-LOK, Bird Cage, Black Nitride Finish, XTSCU8300BK, EDEMO1, Used, Condition Fair , MPN: XTSCU8300BK-EDEMO1 , Code: 20R-UFH-ARBOUP-XTSCU8300BK-EDEMO1
  • XTS Complete Upper Receiver w/o BCG, AR-15, 300 BO, 17.5in, 8.5in, Pistol, 1-8 Twist, 5/8x24 Thread, M-LOK, Bird Cage, Black Nitride Finish, Red, XTSCU8300RD , MPN: XTSCU8300RD , UPC: 767820106724 , Code: 20R-UFH-ARBOUP-XTSCU8300RD
  • XTS Complete Upper Receiver w/o BCG, AR-15, 300 BO, 17.5in, 8.5in, Pistol, 1-8 Twist, 5/8x24 Thread, M-LOK, Bird Cage, Black Nitride Finish, OD Green, XTSCU8300OD , MPN: XTSCU8300OD , UPC: 767820107127 , Code: 20R-UFH-ARBOUP-XTSCU8300OD
  • XTS Complete Upper Receiver w/o BCG, AR-15, 300 BO, 17.5in, 8.5in, Pistol, 1-8 Twist, 5/8x24 Thread, M-LOK, Bird Cage, Black Nitride Finish, Bronze, XTSCU8300BR , MPN: XTSCU8300BR , UPC: 767820106700 , Code: 20R-UFH-ARBOUP-XTSCU8300BR
  • XTS Complete Upper Receiver w/o BCG, AR-15, 300 BO, 17.5in, 8.5in, Pistol, 1-8 Twist, 5/8x24 Thread, M-LOK, Bird Cage, Black Nitride Finish, Silver, XTSCU8300SL , MPN: XTSCU8300SL , UPC: 767820106731 , Code: 20R-UFH-ARBOUP-XTSCU8300SL
  • XTS Complete Upper Receiver w/o BCG, AR-15, 300 BO, 17.5in, 8.5in, Pistol, 1-8 Twist, 5/8x24 Thread, M-LOK, Bird Cage, Black Nitride Finish, Blue, XTSCU8300BL , MPN: XTSCU8300BL , UPC: 767820106694 , Code: 20R-UFH-ARBOUP-XTSCU8300BL
  • XTS Complete Upper Receiver w/o BCG, AR-15, 300 BO, 17.5in, 8.5in, Pistol, 1-8 Twist, 5/8x24 Thread, M-LOK, Bird Cage, Black Nitride Finish, Purple, XTSCU8300PP , MPN: XTSCU8300PP , UPC: 767820106717 , Code: 20R-UFH-ARBOUP-XTSCU8300PP
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