My Best AR-9 Lower Yet

Published on February 7, 2024
Duration: 14:19

This video provides an expert-level guide to building the Hoffman Tactical SL9 AR-9 lower receiver. It details the installation of unique features such as the last round bolt hold open mechanism, a 3D printed ejector, and an over-insertion stop boss for Glock magazines. The guide emphasizes the use of both machined and 3D printed components, offering insights into material choices and assembly techniques for a reliable 9mm AR platform build.

Quick Summary

The Hoffman Tactical SL9 AR-9 lower receiver features a unique last round bolt hold open mechanism that reliably actuates the AR-15 bolt catch. It also incorporates a 3D printed ejector made from Overture Easy Nylon and an over-insertion stop boss to prevent magazine feeding issues.

Chapters

  1. 00:00Initial Shooting Demo
  2. 00:41Close-Quarters Shooting
  3. 01:00Introduction & Build Overview
  4. 01:37Detailed Features: Front Takedown
  5. 02:29Detailed Features: Last Round Bolt Hold Open
  6. 05:07Detailed Features: Ejector
  7. 06:29Detailed Features: Magazine Well
  8. 08:06Detailed Features: Magazine Catch & Pin Removal
  9. 09:03Rear End Features & Compatibility
  10. 12:47Obtaining Digital Files
  11. 14:04Conclusion

Frequently Asked Questions

What is the primary innovation of the Hoffman Tactical SL9 AR-9 lower receiver?

The most significant innovation is its last round bolt hold open mechanism. It uses a clever system involving a magazine follower lever, a hex shaft, and the standard AR-15 bolt catch, ensuring reliable bolt hold open after the last round is fired.

What materials are used for key components in the SL9 build?

The SL9 utilizes a mix of materials. The ejector is 3D printed from Overture Easy Nylon for durability. Front takedown pin plates are typically machined aluminum, though 3D printed options exist. The magazine catch is also 3D printed.

How does the SL9 prevent magazine over-insertion?

The SL9 features an over-insertion stop boss on the left side of the magazine well. This boss prevents Glock magazines from being pushed too far into the receiver, which can cause feeding malfunctions and damage.

Where can I find the digital files to build my own Hoffman Tactical SL9?

Digital files for the SL9 lower receiver are available. The best way to find them is to perform a Google search for 'Hoffman Tactical' to access their website or relevant community forums where assembly guides and files are shared.

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