in reality the difference is much bigger but gets distorted by adaptive microphone

Published on October 30, 2025
Duration: 0:39

This guide demonstrates the audible difference between supersonic and subsonic 9mm ammunition when used with a suppressor. It highlights how suppressors work by slowing gas expansion and explains that subsonic rounds avoid the 'crack' of breaking the sound barrier. The demonstration involves firing a mixed magazine through a suppressed handgun in an indoor range setting.

Quick Summary

The key difference between supersonic and subsonic 9mm ammunition with a suppressor is the 'crack' of breaking the sound barrier. Subsonic rounds travel below this threshold, offering a quieter shot, while supersonic rounds produce a distinct sonic boom. Suppressors work by slowing gas expansion, reducing overall noise and flash.

Chapters

  1. 00:00Ammunition Introduction
  2. 00:04Suppressor Mechanics Explained
  3. 00:21Live Fire Demonstration

Frequently Asked Questions

What is the main audible difference between supersonic and subsonic 9mm ammunition when using a suppressor?

When suppressed, subsonic 9mm ammunition is significantly quieter because it travels below the speed of sound, avoiding the sharp 'crack' that supersonic rounds produce as they break the sound barrier. This makes subsonic rounds ideal for maximum noise reduction.

How does a firearm suppressor work to reduce noise?

A suppressor works by containing and slowing down the rapid expansion of hot propellant gases after a bullet leaves the barrel. This process reduces the overall sound pressure wave and muzzle flash, making the firearm quieter.

What types of 9mm ammunition were compared in the video?

The video compared Sellier & Bellot 9mm Luger FMJ (115gr) standard supersonic ammunition with Sellier & Bellot 9mm Luger Subsonic (140gr) ammunition, demonstrating their audible differences when fired through a suppressed handgun.

What accessories were visible on the handgun?

The handgun featured an MFT PX9 suppressor mounted on the barrel and a Holosun red dot optic mounted on the slide. These accessories enhance the shooting experience by reducing noise and improving target acquisition.

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