This Model Doesn’t Exist - Most Powerful Carry Gun for Its Size

Published on December 11, 2025
Duration: 9:13

This video explores a custom Smith & Wesson M&P Shield build chambered in .357 SIG, focusing on maximizing power and reliability for concealed carry. The presenter details how to convert a .40 S&W Shield by swapping the barrel and discusses the advantages of .357 SIG, including its ballistics and feeding reliability due to its bottleneck design. The build incorporates aftermarket parts like an Apex trigger and Mag Guts for increased capacity, offering a potent and affordable self-defense option.

Quick Summary

The Smith & Wesson M&P40 Shield can be converted to a powerful .357 SIG concealed carry pistol by swapping the barrel. This build offers superior ballistics, capable of defeating soft body armor, and enhanced feeding reliability due to the bottleneck cartridge design. Aftermarket parts like Apex triggers and Mag Guts can further improve performance and capacity.

Chapters

  1. 00:06Intro & Channel Update
  2. 00:33The Concept: A Non-Existent Gun
  3. 00:44Safety First: Snap Caps
  4. 01:00The M&P Shield Platform
  5. 01:21M&P40 Shield Price & Caliber
  6. 01:409mm vs. .40 S&W Preference
  7. 01:51Shield Plus Upgrades
  8. 01:59Performance Center 9mm Shield
  9. 02:10Focus on Power: .357 SIG
  10. 02:18Double Tap Ammunition
  11. 02:45Double Tap Discount Code
  12. 02:57Performance Center .40 S&W Shield
  13. 03:31M&P45 Shield Discussion
  14. 04:04The M&P40 Shield in .357 SIG
  15. 04:12Performance Center .357 SIG Barrel
  16. 04:22Performance Center Porting
  17. 04:31Recoil Management in Performance Center Models
  18. 04:48Why .357 SIG?
  19. 04:51Is .357 SIG a Dead Round?
  20. 04:56Specialty Ammo Sources
  21. 05:00Civil Liberty Ammunition
  22. 05:13.357 SIG vs. Body Armor
  23. 05:24.357 SIG Ballistics Proven
  24. 05:35Self-Defense Encounter Dynamics
  25. 05:44First Shot Importance
  26. 06:06Unported vs. Ported Shield
  27. 06:08Apex Trigger Upgrade
  28. 06:12SpinFirearms.com & Apex
  29. 06:21Shield Plus Style Build
  30. 06:27Mag Guts for Capacity
  31. 06:30Using .40 S&W Magazines
  32. 06:36Mag Guts Capacity: 7+1
  33. 06:42Extended Mag Capacity: 8+1
  34. 06:489 Rounds of .357 SIG
  35. 06:59Affordable .357 SIG Shield Build
  36. 07:03TR Enabling Barrels
  37. 07:147+1 Capacity with Base Plate
  38. 07:22Training with .40 S&W
  39. 07:35.357 SIG Recoil & Flip
  40. 07:51Affordable Training Method
  41. 07:54Why .357 SIG? Reliability
  42. 08:07Bottleneck Cartridge Design
  43. 08:12.357 SIG Construction
  44. 08:23FBI Preference for .357 SIG
  45. 08:29Bottleneck Round Malfunction Rates
  46. 08:39Shield .357 SIG 7+1 Carry
  47. 08:46Capacity, Reliability, Power
  48. 08:51Year-Round Carry Gun
  49. 08:55Winter Performance

Frequently Asked Questions

How can you build a powerful concealed carry pistol from a Smith & Wesson M&P Shield?

You can build a powerful concealed carry pistol by converting a Smith & Wesson M&P40 Shield to .357 SIG by replacing the barrel. Performance Center barrels offer porting for recoil reduction, and aftermarket parts like Apex triggers and Mag Guts can enhance performance and capacity.

What are the advantages of the .357 SIG cartridge for self-defense?

.357 SIG offers superior power and penetration compared to 9mm and .40 S&W, capable of defeating soft body armor. Its bottleneck design also ensures feeding reliability, minimizing malfunctions in critical situations.

Is .357 SIG ammunition readily available?

.357 SIG is considered a less common caliber, meaning ammunition is not widely available in local stores. It typically needs to be specialty ordered online from manufacturers like Double Tap, Buffalo Bore, or Civil Liberty.

How can magazine capacity be increased on a .357 SIG Shield build?

Magazine capacity can be increased on a .357 SIG Shield build using .40 S&W magazines combined with a Mag Guts kit, typically yielding 7+1 rounds. With an extended base plate, this can be increased to 8+1.

Related News

All News →

More Reviews Videos You Might Like

More from SPN Firearms

View all →