B&T APC9-SD - The Swiss MP5-SD

Published on December 5, 2019
Duration: 20:56

This guide details the disassembly process to inspect the unique ported barrel system of the B&T APC9-SD. The video, presented by an established firearms expert, demonstrates how the ported barrel works in conjunction with the integral suppressor to reduce supersonic 9mm rounds to subsonic velocities, effectively mitigating the sonic crack. The expert also touches on magazine reliability and the firearm's internal mechanics.

Quick Summary

The B&T APC9-SD achieves subsonic velocities with standard 9x19mm ammunition using a ported barrel that bleeds gas into its integral suppressor. This system effectively slows bullets below the speed of sound, eliminating the sonic crack while allowing the use of affordable ammo.

Chapters

  1. 00:00Introduction to APC9 SBR
  2. 01:08The MP5-SD Concept
  3. 03:09APC9-SD Features (Gen 1)
  4. 06:29Disassembly and Ported Barrel
  5. 09:33Chronograph Testing
  6. 13:51Magazine Failure and Internals
  7. 15:56Conclusion

Frequently Asked Questions

How does the B&T APC9-SD achieve subsonic velocities with standard ammunition?

The B&T APC9-SD uses a unique ported barrel design located just ahead of the chamber. These ports bleed off propellant gases into the integral suppressor, slowing the bullet down to subsonic speeds before it exits, effectively eliminating the sonic crack.

What is the main advantage of the B&T APC9-SD's design?

The primary advantage is its ability to use standard, affordable 9x19mm ammunition and still achieve effective suppression, turning supersonic rounds into subsonic ones without needing specialized ammunition. This offers high-quality Swiss engineering with practical ammunition compatibility.

What technical specifications were highlighted for the B&T APC9-SD?

Key specs include a 5.74-inch barrel length, a 30-round capacity, blowback operation, and the integral suppressor system. The MSRP was noted at approximately $3300 with the silencer included.

Were there any reliability issues observed with the B&T APC9-SD?

During testing, a polymer B&T magazine follower tab broke, preventing the bolt from locking open on an empty magazine. This indicates a potential point of failure in the magazine's polymer components.

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