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Questions & Answers
Does this come with all necessary mounting parts. Castle nut, end plate ect.? Expert Answer

The kit contains

T6 6061 Aluminum A2 Buffer Tube
Rifle Length .308 Cal Chrome Buffer Spring
A2 .308 Cal Buffer,

but does not include the castle nut or end plate.

Mark H.

by Mark H., Gear Expert, December 18, 2017
Will this fit an armalite ar10?

This will fit on the Armalite receiver, but there's more details we need to give you an accurate answer whether you have an Armalite AR-10 A or B Series AR-10 as the bolt carrier is different and requires different length buffer tubes. Send us an email at techsales@opticsplanet.com and we can help you identify what you have and get you set up with the correct extension.

by Brandon, Verified Owner, February 17, 2021
Customer Reviews
Helpful Negative Review
Good tube, but.. by Lop, Verified Owner, July 23, 2019
The tube and spring are pretty solid and are durable. Big issue though. The buffer is about 2mm longer then other rifle buffers I have compared them too. Extra length was causing stovepipe jams and wasn’t allowing cycling.
5/5 found this helpful
Most Recent Reviews
Buffer didnt last 65 rounds. by Dc190, Verified Owner, April 25, 2025
I started having issues with feeding in my 6.5 AR and i got home to clean it and found the buffer in multiple pieces. Going to need a replacement.
Most Recent Reviews
Aero M5 no bueno by Jerico23ban, Verified Owner, December 29, 2019
Full disclosure I have aero M5 build with fail zero chrome bolt carrier and this sprint is more than double the strength needed to cycle so that was first issue... then buffer roll pin loosened up and gouged the buffer tube almost locking it in place
0/1 found this helpful
Most Recent Reviews
GUNTEC USA Stock tube AR-10 by Nicholas, January 21, 2017
doNice solid piece of equipment. Reliable product and well built. Took awhile to receive to product as it was on backorder. Looking forward to using it for years to come on my AR-10 Build. It does feel a little heavy, however it is built to last.
0/3 found this helpful
Most Recent Reviews
Poor internals by Straws, Verified Owner, August 2, 2019
Product was shipped to me spring of 2018. Thanks to OPTICS PLANET it arrived quickly and on time. However Guntec left the inside of the tube ribbed with an improper buffer spring and it caused my AR-10 to have unreliable cycling. Apologies for the la...
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Read All 5 Reviews
Color: Black Gun Model: AR-10 Condition: New

Code: 2AH-RBT-A2TUBESET-308-EE

MPN: A2TUBESET-308

UPC: 714569648770

List: $71.92Save 23%
$55.18

Product Info for Guntec USA AR-10/LR-308 Rifle Stock Tube Kit

A2 Rifle Tube Kit T6 6061 Aluminum A2 Buffer Tube Rifle Length .308 Cal Chrome Buffer Spring A2 .308 Cal Buffer Drop In Readyimage

Specifications for Guntec USA AR-10/LR-308 Rifle Stock Tube Kit:

Manufacturer: Guntec USA
Color: Black
Gun Model: AR-10
Condition: New

Package Contents:

  • Guntec USA AR-10/LR-308 Rifle Stock Tube Kit

Guntec USA AR-10/LR-308 Rifle Stock Tube Kit Orderable Models

List of Orderable Models

  • Guntec USA AR-10/LR-308 Rifle Stock Tube Kit, .308 Cal, A2TUBESET-308 , MPN: A2TUBESET-308 , UPC: 714569648770 , Code: 2AH-RBT-A2TUBESET-308-EE
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