Aero Precision Receiver Extension Buffer Tube Assembly 6-Position Mil-Spec Diameter AR-15 Carbine Aluminum Black

The Aero Precision AR-15 Carbine 6-Position Mil-Spec Buffer Tube Assembly gives you the foundation to tune your AR's recoil impulse and reliability exactly how you need it. Built from 7075-T6 aluminum and finished in black, this mil-spec buffer tube is machined to tight tolerances and designed for the rigors of the range and field. Whether you're running a pistol-length or carbine-length gas system, a properly weighted buffer makes the difference between a rifle that runs smooth and one that batters itself apart—especially on short-stroke setups prone to overgassing.

This assembly ships complete with everything you need to finish the rear end of your build: the buffer tube itself, a buffer spring, end plate, and castle-lock nut. The six-position design lets you dial in length of pull from a compact cheek weld to a full stock extension, so it works for shooters of all sizes and gear configurations. The real tuning happens when you pair this tube with the right buffer weight for your gas system, reducing excessive wear on carrier and bolt while keeping felt recoil manageable.

Aero Precision's reputation for precision manufacturing shows in every detail here. The aluminum tube is hard-coat anodized for durability, and the mil-spec dimensions ensure compatibility with standard AR furniture and parts. This is the kind of no-nonsense component that works on a duty rifle, a match gun, or a hunting carbine—it does its job without pretense.

Key Features

• 7075-T6 aluminum construction for strength and light weight
• Six-position adjustable buttstock design for customizable length of pull
• Mil-spec dimensions ensure broad compatibility with aftermarket stocks and furniture
• Complete assembly includes buffer spring, end plate, and castle-lock nut—ready to install
• Black hard-coat anodize finish for corrosion resistance and durability
• Designed to work with various buffer weights to fine-tune gas system performance

Specifications

Frequently Asked Questions

What's included with this buffer tube assembly?

The assembly comes complete with the mil-spec buffer tube, a buffer spring, an end plate, and a castle-lock nut. You'll have everything needed to install it on your lower receiver; you just need to source your preferred buffer weight separately if you want to tune the system.

Will this work on my AR-15?

This is designed for AR-15 carbine-length gas systems and features mil-spec dimensions, so it will work with standard AR-15 lowers and aftermarket stocks designed for mil-spec tubes. Compatibility with specialized or non-standard setups depends on their specific requirements.

What's the difference between buffer weights, and why does it matter?

Different buffer weights (measured in ounces) slow down the cycling speed of your bolt carrier group. A heavier buffer reduces the felt recoil impulse and can help tame an overgassed short-stroke system. The right weight depends on your gas system length and tuning goals—that's why Aero offers this tube as part of a complete kit ecosystem with various buffer options.

How many positions does the buttstock adjust to?

This mil-spec tube supports six-position adjustable stocks, giving you flexibility to set your length of pull for body armor, different shooting positions, or simply to fit different shooters.