Full Custom Browning Hi-Power MKIII .40S&W Converted to 9mm

Published on June 16, 2026
Duration: 3:55

This video details a custom Browning Hi-Power MKIII, originally a .40 S&W, converted to 9mm. Key modifications include a KKM 5.4-inch barrel for improved 9mm performance, Trijicon HD front sight, Holosun EPS Carry optic with integrated rear sight, Streamlight TLR-7 compatibility, RDIH extended slide release, and a custom trigger job resulting in a single-stage, light-break trigger with a positive reset. The video also explains the unique RDIH SFS system for carrying cocked-and-locked discreetly.

Quick Summary

This custom Browning Hi-Power MKIII, originally .40 S&W, is converted to 9mm with a KKM 5.4-inch barrel for optimal performance. It features a Holosun EPS Carry optic, RDIH SFS system for discreet cocked-and-locked carry, and a custom single-stage trigger with a crisp reset.

Chapters

  1. 00:00Introduction to Custom Hi-Power
  2. 00:05.40 S&W to 9mm Conversion Details
  3. 00:11KKM 5.4" Barrel for 9mm Performance
  4. 00:30Front Sight: Trijicon HD
  5. 00:41Optic: Holosun EPS Carry with Rear Sight
  6. 00:55Accessory Rail and Light Compatibility (TLR-7)
  7. 01:04RDIH Extended Slide Release
  8. 01:10RDIH SFS System Explained
  9. 01:22Custom Trigger Job: Single Stage, Light Break, Reset
  10. 01:47High Undercut Trigger Guard for Grip
  11. 01:56Identifying MKIII Features (Magwell Serrations)
  12. 02:04Cast Frame Strength (MKIII)
  13. 02:10Blue and Black Seracote Finish
  14. 02:18TLR-7 Light Demonstration
  15. 02:30Back in Business: New Shop Operations
  16. 02:40Conclusion and Q&A

Frequently Asked Questions

What are the key modifications on this custom Browning Hi-Power MKIII?

This Browning Hi-Power MKIII was originally a .40 S&W converted to 9mm. It features a KKM 5.4-inch barrel, Trijicon HD front sight, Holosun EPS Carry optic, RDIH extended slide release, a custom single-stage trigger job with a crisp reset, and a high undercut trigger guard for improved grip.

How does the RDIH SFS system on the Hi-Power work?

The RDIH SFS system allows for cocked-and-locked carry while appearing de-cocked. To engage, you push the hammer forward, which automatically raises the safety. To fire, you push down on the safety, and the hammer pops back, readying the pistol.

What is the benefit of the 5.4-inch KKM barrel in a 9mm Hi-Power conversion?

The 5.4-inch KKM barrel is considered an optimal length for 9mm conversions in a factory Hi-Power slide. It helps maximize powder burn and pressure build-up, leading to improved ballistic performance for the 9mm cartridge.

What are the characteristics of the custom trigger job on this Hi-Power?

The custom trigger job results in a single-stage trigger with no take-up, a very light break, minimal over-travel, and a distinct, audible reset. This significantly enhances the shooting experience by providing precise control and immediate feedback.

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