What is a mil-spec buffer tube?

A mil-spec buffer tube is a 1.14” diameter AR-15 component that connects the stock to the receiver. It provides a solid base for the recoil spring and buffer, and ensures compatibility with mil-spec stocks.

Will a mil-spec buffer tube fit a commercial AR-15 stock?

No. Mil-spec buffer tubes are slightly smaller in diameter than commercial ones. You must use a mil-spec-compatible stock with a mil-spec tube.

Mil-Spec Buffer Tube | AR-15 Buffer Tubes & Kits

Name: Mil-Spec Buffer Tube
Brand: Mounts Plus
Availability: InStock

**ATI AR-15 Buffer Tube - Mil-Spec Buffer Tube** $43.28

**ATI AR-15 Mil-Spec Buffer Tube Package** $63.12

**BCM Mil-Spec Carbine Buffer Tube** $50.60

**BCM Milspec Carbine Stock Hardware MOUNTING KIT (Mil-Spec)** $66.69

**UTG PRO AR15 6-Position Receiver Extension Tube, Mil-Spec, Matte Black** $30.38

**UTG PRO AR15 6-Position Receiver Extension Tube ‚Äì Mil-Spec, FDE Cerakote¬Æ** $44.48

**Luth-AR Carbine Buffer Tube ‚Äì Mil-Spec ‚Äì 6 Position** $37.98

**DELTAC AR-15 Buffer Tube Mil-Spec - MADE IN USA** $27.49

**Timber Creek Buffer Tube - Mil-Spec AR15 Buffer Tube** $31.99

**Timber Creek Carbon Fiber Buffer Tube - Mil-Spec AR-15 Buffer Tube Kit** $71.99

**VISM AR-15 Buffer Tube / Aluminum Mil Spec Buffer Tube with Castle Nut** $18.99

**Aero Precision AR15/AR10 Enhanced Carbine Buffer Tube - Kodiak Brown Anodized** $57.48

**Aero Precision AR15/AR10 Enhanced Carbine Buffer Tube - OD Green Anodized** $57.48

**BATTLEARMS¬Æ MIL-SPEC 6-Position Carbine Buffer Tube** $47.73

**Nordic Components Mil-Spec Buffer Tube ‚Äì 6 Position** $49.18

**Kak A5 Style AR15 Buffer Tube ‚Äì 9-Position** $42.63

**San Tan Tactical AR-15 Enhanced Buffer Tube Kit | Carbine | 6-Position** $105.36

**CMC Triggers AR-15 Mil-Spec Carbine Buffer Tube Kit ‚Äì Enhanced QD** $67.22

**Spike‚Äôs Tactical Mil-Spec 6-Position Buffer Tube** $48.13

**Deltac AR-15 Mil Spec Buffer Tube Kit with Dual Loop Sling End Plate** $79.92

**Spike‚Äôs Tactical Mil-Spec 6-Position Buffer Tube Assembly** $97.84

**Spike's Buffer Tube Assembly Pistol** $85.46

**Phase5 AR15 Pistol Buffer Tube Complete Assembly (PBT-CA)** $67.47

Mil-Spec Buffer Tube – Reliable AR-15 Buffer Tubes for Tactical Builds

A Mil-Spec Buffer Tube is a critical component in any AR-15 build, directly affecting the fit of your stock and the overall reliability of your rifle. Whether you're assembling a complete rifle or upgrading a commercial-spec tube, Mounts Plus offers a full selection of mil-spec carbine buffer tubes trusted by builders, professionals, and shooters across the country.

We carry mil-spec AR-15 buffer tubes from top brands like Luth-AR, UTG PRO, VLTOR, Aero Precision, and more—all built to military dimensions for a snug, secure fit with your collapsible stock.

✅ Why Choose a Mil-Spec Buffer Tube?

Choosing the correct buffer tube is critical for compatibility and performance. Here’s why mil-spec buffer tubes are the gold standard:

📏 Standardized Diameter (1.14") – Ensures fit with all mil-spec AR-15 stocks
🛠️ 7075-T6 or 6061-T6 aluminum – Military-grade strength and corrosion resistance
🔩 Anodized Finish – Hardcoat for maximum durability
🔄 Six-position notches – Allow stock length adjustments for any shooter
🔧 Threaded to fit any mil-spec lower receiver

Don’t settle for commercial tubes that cause stock wobble. Mil-spec ensures a tight lockup and professional-grade performance.

📦 What’s in a Complete Mil-Spec Buffer Tube Kit?

We offer buffer tubes only as well as complete buffer tube kits, including:

✅ Mil-spec diameter buffer tube
✅ Carbine buffer spring
✅ Carbine buffer (standard, H1, or H2)
✅ End plate & castle nut
✅ Optional QD sling mount compatibility

Need help choosing the right configuration? Our support team is ready to assist.

📊 Compare Top Mil-Spec Buffer Tubes

Brand	Material	Finish	Kit Option	Price
UTG PRO	6061-T6 Alu.	Black anodized	Yes	$44.95
Luth-AR	6061-T6 Alu.	Black anodized	Yes	$49.95
Aero Precision	7075-T6 Alu.	Mil-Spec Ano.	Tube Only	$34.99
VLTOR A5	7075-T6 Alu.	Extended Tube	Yes	$95.99

🔧 Installation Tips

Always use a proper armorer’s wrench to torque the castle nut
Don’t forget to stake the end plate after torquing
Ensure buffer spring and buffer match your barrel length/gas system
Consider adding a QD end plate for sling compatibility

❓ Frequently Asked Questions

What’s the difference between mil-spec and commercial buffer tubes?

Mil-spec buffer tubes have a diameter of 1.14” and are made to tighter tolerances. Commercial tubes are slightly larger (1.17”) and less standardized, which can cause stock wobble or fitment issues.

Will a mil-spec buffer tube work on my AR-15?

Yes, as long as your lower is mil-spec (which most are), this tube will fit. Just make sure you’re using a mil-spec compatible stock.

What’s the best material for a buffer tube?

7075-T6 aluminum offers the best strength-to-weight ratio and is standard for military contracts. 6061-T6 aluminum is more affordable but still durable for most civilian builds.

🛒 Shop Mil-Spec Buffer Tubes at Mounts Plus

Mounts Plus offers high-quality AR-15 buffer tubes and kits built to military specifications. Whether you’re upgrading or building from scratch, you’ll get:

✅ Military-spec fit & finish
✅ Premium brands in stock
✅ Complete kits or standalone tubes
✅ Fast U.S. shipping and expert support