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Ar-15/M16 Mil-Spec Buffer Tube Assembly - M4 Mil-Spec Buffer Tube Assembly
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$54.99
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SKU: 080001039
Overview
This receiver extension assembly is built for standard AR-15/M16 lower receivers and provides a six-position setup for a carbine-style build. It includes the buffer tube, receiver lock plate, castle nut, carbine buffer, and carbine buffer spring, giving you the core components needed for assembly in one package. The tube is mil-spec diameter and made from 6061 aluminum, while the spring is 17-7 stainless steel and the buffer weighs 3 oz. It is a straightforward option for hunters and shooters setting up or replacing a compatible rifle stock interface without extra parts to source separately.
Why Hunters Choose the Brownells
Six-position Receiver
Extension assembly for AR-15/M16/M4 setups
Includes Buffer
Tube, lock plate, castle nut,
Mil-spec Diameter
Fits standard AR-15/M16 lower receivers
Receiver Extension
Is made from 6061 aluminum
Carbine Buffer
Weighs 3 oz for a
Key Features
- Six-position AR-15/M16/M4 receiver extension assembly
- Includes buffer tube, receiver lock plate, castle nut, carbine buffer, and buffer spring
- Mil-Spec diameter receiver extension
- Buffer tube made from 6061 aluminum
- Carbine buffer weight is 3 oz
- Buffer spring made from 17-7 stainless steel
- Fits standard AR-15/M16 lower receivers
Best Used For
- Standard AR-15/M16/M4 lower receiver builds needing a six-position receiver extension assembly
- Hunters assembling a carbine setup with included buffer, spring, lock plate, and castle nut
- Users replacing a mil-spec diameter buffer tube assembly on compatible lower receivers
- Builders wanting a Brownells receiver extension kit with the core recoil components included
Specifications
| Buffer Spring Material | 17-7 stainless steel |
|---|---|
| Buffer Tube Diameter | Mil-Spec |
| Buffer Tube Material | 6061 aluminum |
| Carbine Buffer Weight | 3 oz |
| Fits Standard Ar 15m16 Lower Receivers | Yes |
| Includes Carbine Buffer | Yes |
| Includes Carbine Buffer Spring | Yes |
| Includes Lock Nutcastle Nut | Yes |
| Includes Receiver Extensionbuffer Tube | Yes |
| Includes Receiver Lock Plate | Yes |
| Receiver Extension Type | AR-15/M16/M4 receiver extension assembly |
| Six Position | Yes |
Pros
- Six-position receiver extension assembly for AR-15/M16/M4 setups.
- Includes buffer tube, lock plate, castle nut, buffer, and spring.
- Mil-spec diameter fits standard AR-15/M16 lower receivers.
- Receiver extension is made from 6061 aluminum.
- Carbine buffer weighs 3 oz for a complete assembly.
- Uses a 17-7 stainless steel carbine buffer spring.
Considerations & Trade-offs
- This is a six-position receiver extension assembly, so adjustment is limited to the included position range rather than a fixed-length setup.
- It is specified for standard AR-15/M16 lower receivers; compatibility outside that platform is not indicated in the product data.
- The assembly includes the buffer tube, lock plate, castle nut, buffer, and spring, but does not include other stock or lower-receiver components.
- The buffer tube is mil-spec diameter, so it is intended for mil-spec-compatible setups rather than all receiver extension styles.
Suggested Comparisons
- AR-15/M16 receiver extension assemblies
- Carbine buffer and spring kits
- Mil-spec lower receiver parts
- AR-15/M4 stock mounting components
Suggested Accessories
- Armorer's wrench
- Receiver end plate
- Carbine buffer spring
- Lower receiver parts kit
Frequently Asked Questions
What is included in this buffer tube assembly?
The assembly includes a Mil-Spec receiver extension/buffer tube, receiver lock plate, lock-nut/castle nut, carbine buffer, and carbine buffer spring.
Will this fit a standard AR-15 lower receiver?
Yes. The product data states it fits standard AR-15/M16 lower receivers.
Is this a six-position receiver extension?
Yes. It is described as a six position AR-15/M16/M4 receiver extension assembly.
What materials are specified for the buffer tube and spring?
The buffer tube is listed as 6061 aluminum, and the buffer spring is 17-7 stainless steel.
What is the carbine buffer weight?
The carbine buffer weight is listed as 3 oz.