Primary Weapons Enhanced Pistol Buffer Tube with Castle Nut - 4G2BTPB-1F

The Primary Weapons Enhanced Pistol Buffer Tube is a refined take on the mil-spec standard, engineered for shooters who want a reliable, lightweight receiver extension without compromise. Built from 7075 aluminum and finished with mil-spec hard anodizing, this buffer tube combines smooth cycling performance with practical weight savings—roughly 1 ounce lighter than traditional mil-spec tubes. Whether you're building an AR pistol for the range, home defense, or general duty work, PWS's attention to detail shows in the engineering.

The extended carrier support lip is designed to promote more consistent cycling across various ammunition types and shooting conditions. A series of lightening cuts runs the length of the tube, reducing mass without weakening structural integrity. The fluted design also serves a practical purpose: it helps shed debris and fouling that can accumulate during extended shooting sessions, keeping your action running clean. The hard-anodized Type III Class 2 finish resists corrosion and stands up to both range and field use.

This kit ships complete with PWS's ratchet lock castle nut and end plate, so you have everything needed to install it on your lower receiver. The ratchet lock design simplifies installation and ensures a secure, repeatable fit. If you're upgrading an existing build or assembling an AR pistol from scratch, this tube gives you mil-spec reliability with thoughtful refinements that matter during long shooting sessions or when conditions get rough.

Key Features

• Impact-extruded 7075 aluminum construction with mil-spec hard anodizing (Type III Class 2)
• Extended carrier support lip for smoother, more consistent cycling
• Lightening cuts reduce weight by approximately 1 ounce compared to standard mil-spec tubes
• Fluted design helps clear debris and fouling during operation
• Includes PWS ratchet lock castle nut and end plate for complete installation
• Mil-spec tube diameter for universal lower receiver compatibility

Specifications

Frequently Asked Questions

Is this buffer tube compatible with standard AR pistol lower receivers?

Yes. This tube is mil-spec diameter and designed for universal compatibility with any lower receiver that accepts a standard pistol buffer tube.

What's included in this kit?

The kit includes the buffer tube itself, a PWS ratchet lock castle nut, and an end plate—everything you need to install it on your lower receiver.

How much weight does the fluted design save?

The lightening cuts and fluted geometry reduce weight by approximately 1 ounce compared to traditional mil-spec pistol buffer tubes.

What does the extended carrier support lip do?

The extended lip promotes smoother and more reliable cycling by providing better support to the bolt carrier as it travels through the tube, particularly helpful with a wide range of ammunition types and shooting conditions.