XTS AR-15 Mil-Spec 6-Position Buffer Tube Assembly Black - XTS-BTA-MIL

XTS Buffer Tube Complete Assembly Includes Buffer Buffer Tube Buffer Spring Castle Nut End Plate Fits AR 15 Rifles Black XTS BTA MIL UPC 767820091167

Product Description

The XTS Complete Mil-Spec Buffer Tube Assembly in Matte Black (MPN: XTS-BTA-MIL) is an all-in-one lower receiver extension kit engineered to provide seamless stock fitment, reliable action cycling, and proper recoil mitigation for standard AR-15 platforms. Precision-machined from high-strength 6061-T6 aircraft aluminum and finished in a durable hardcoat anodized black, the 6-position receiver extension tube accepts all standard Mil-Spec carbine buttstocks and stabilizing braces.

This turnkey completion kit includes a standard 3.0 oz carbine recoil buffer, a heavy-duty heat-treated carbon steel carbine buffer spring, a steel castle nut, and a standard steel lower receiver end plate. Designed for consistent BCG cycling, proper bolt catch engagement, and reduced internal wear, the XTS-BTA-MIL provides smooth travel for full-auto and semi-automatic bolt carrier groups across standard 5.56 NATO, .223 Rem, and 300 AAC Blackout builds.

Whether assembling a new custom AR-15 lower receiver from a stripped housing or replacing worn extension components on a duty carbine, the XTS-BTA-MIL delivers clean thread engagement and simple installation. Backed by XTS quality assurance, it represents an unbeatable value for custom bench builds and emergency armorer replacement inventories.

Armorer Bench Notes & Real-World Staging Guidance:
Fitment Matrix: Fits standard AR-15 pattern lower receivers (Mil-Spec dimensioned) chambered in 5.56 NATO, .223 Rem, 300 Blackout, 6.5 Grendel, and 350 Legend. Compatible with all Mil-Spec dimensioned adjustable carbine buttstocks (Magpul, BCM, B5 Systems, MFT). (Note: Not compatible with Commercial-spec stocks which feature a larger tube diameter, nor compatible with AR-10 / LR-308 extended depth receiver extension requirements unless utilizing a short 308 buffer).

1. Perform a complete firearm safety check: drop the magazine, pull the charging handle rearward, lock the action open, and visually inspect the chamber to verify zero live rounds are present.
2. Thread the castle nut onto the XTS buffer tube with the notched staking spanner ring facing rearward toward the buttstock end.
3. Slide the steel end plate onto the buffer tube with the alignment alignment index key facing forward toward the receiver frame.
4. Thread the buffer tube into the rear lower receiver housing until it depresses and captures the buffer retainer pin and spring without binding.
5. Slide the end plate forward into the rear lower receiver index notch, thread the castle nut forward against the end plate, and hand-tighten.
6. Using an AR-15 castle nut wrench, torque the castle nut to manufacturer specification (38–40 ft-lbs) and stake the end plate steel into one of the castle nut notches using a center punch.
7. Insert the carbine buffer spring and 3.0 oz carbine buffer into the tube until captured by the buffer retainer pin, then slide your Mil-Spec buttstock onto the extension tube.

Key Features

• 6061-T6 Aluminum Construction: Precision-milled aircraft aluminum extension tube delivers extreme structural strength and lightweight durability.
• Standard 6-Position Mil-Spec Profile: Allows precise length-of-pull adjustability with standard Mil-Spec adjustable stocks and braces.
• Complete Turnkey Assembly Kit: Includes buffer tube, 3.0 oz carbine buffer, carbine spring, castle nut, and receiver end plate out of the box.
• Type III Hardcoat Anodized Black Finish: Provides superior corrosion protection, scratch resistance, and low surface friction.
• High-Tensile Steel Carbine Spring: Heat-treated spring ensures smooth cycling and positive battery closure under sustained fire.
• Universal AR-15 Lower Compatibility: Drops seamlessly into all standard Mil-Spec forged and billet 5.56/.223 lower receivers.

Product Specifications

• Brand: XTS (Xtreme Tactical Sports / DMA Inc.)
• Model/Series: Complete Mil-Spec Buffer Tube Assembly Kit
• MPN / SKU: XTS-BTA-MIL
• UPC: 767820091167
• Tube Diameter: Mil-Spec Standard (1.148 Inches)
• Positions: 6-Position Receiver Extension
• Platform Compatibility: AR-15 / M4 Lower Receivers
• Buffer Mass: 3.0 oz (Standard Carbine Buffer)
• Materials: 6061-T6 Aluminum Tube / Steel Nut, Spring, End Plate
• Finish / Color: Matte Black Hardcoat Anodized
• Total Kit Weight: 9.8 oz
• Country of Origin: USA / Imported