Inside a One-of-a-Kind Prototype Submachine Gun with firearms expert Jonathan Ferguson

Published on July 16, 2025
Duration: 19:24

This entry details the Sayer's SMG, a unique prototype submachine gun from the Royal Armouries' collection. Expert Jonathan Ferguson provides an in-depth analysis of its 'parts bin' construction, utilizing Sterling SMG magazines and L1A1 SLR furniture. The video highlights its sophisticated, albeit crude, gas-unlocked, roller-delayed blowback action, a design predating many modern counterparts. Ferguson's expert assessment underscores the weapon's significance as a testbed for advanced operating principles.

Quick Summary

The Sayer's SMG is a unique prototype submachine gun from the Royal Armouries, identified by expert Jonathan Ferguson. It's a 'parts bin' build using Sterling SMG magazines and L1A1 SLR furniture, featuring a sophisticated gas-unlocked, roller-delayed blowback action. This design, predating many modern firearms, showcases experimental firearm development.

Chapters

  1. 00:00Introduction to the Unknown Prototype
  2. 01:03Identifying Donor Parts
  3. 02:31Construction and Origin
  4. 04:35Internal Mechanics: Trigger and Hammer
  5. 06:00Gas Operation Discovery
  6. 07:48Disassembly and Gas System Confirmation
  7. 09:21Roller-Locking Mechanism
  8. 11:25Final Assessment

Frequently Asked Questions

What is the Sayer's SMG?

The Sayer's SMG is a unique prototype submachine gun from the Royal Armouries' collection, designed by John Sayer of Interarms UK. It's a 'parts bin' build featuring Sterling SMG magazines and L1A1 SLR furniture, notable for its gas-unlocked, roller-delayed blowback action.

What operating system does the Sayer's SMG use?

The Sayer's SMG employs a sophisticated gas-unlocked, roller-delayed blowback operating system. Gas pressure from the chamber area is used to unlock the rollers, allowing the bolt to cycle, a design predating many modern firearms.

What parts were used in the Sayer's SMG prototype?

The Sayer's SMG is a 'parts bin' creation, utilizing a 34-round Sterling SMG magazine and furniture (pistol grip and handguards) from a British L1A1 SLR. The receiver itself is constructed from sheet metal plates.

Who is Jonathan Ferguson and why is his assessment authoritative?

Jonathan Ferguson is the Keeper of Firearms & Artillery at the Royal Armouries. His authority is demonstrated through detailed mechanical disassembly, historical context of the collection, and comparisons to obscure historical locking systems, providing an expert-level analysis.

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