The ugliest rifle you didn't know you would love - Stgw.57 / PE57

Published on November 15, 2020
Duration: 39:33

This guide details the field stripping and reassembly of the Stgw.57 / PE57 rifle, a complex firearm known for its roller-delayed blowback system and unique chamber design. Expert instructor Tim provides a high-level overview of the disassembly process, emphasizing the intricate components like the fluted chamber and bolt bounce reduction ring. Proper reassembly requires careful attention to the offset firing pin and bolt carrier group orientation.

Quick Summary

The Stgw.57 / PE57 rifle employs a sophisticated roller-delayed blowback operating system, enhanced by a unique fluted chamber featuring a ring that deforms the case neck. This design effectively slows bolt travel and prevents bolt bounce during automatic fire, contributing to its distinct ejection pattern and overall reliability.

Chapters

  1. 00:00Introduction & K31
  2. 03:06Stgw.57 / PE57 Overview
  3. 03:43Operating Principle
  4. 06:23Magazines and Variants
  5. 07:53Unique Ejection Pattern
  6. 10:32Intricate Sighting System
  7. 14:52Bipod and Multi-Role Capability
  8. 16:18Grenade Launching Features
  9. 20:55DMR Role and Scope Mounting
  10. 22:54Chamber Engineering and Bolt Bounce
  11. 29:11Field Stripping and Internals

Frequently Asked Questions

What is the operating principle of the Stgw.57 / PE57 rifle?

The Stgw.57 / PE57 operates using a roller-delayed blowback system, similar in principle to the CETME and G3 rifles, but with unique Swiss engineering refinements. This system uses rollers to delay the opening of the bolt, allowing gas pressure to drop before extraction.

What makes the Stgw.57 / PE57's chamber unique?

The Stgw.57 / PE57 features a fluted chamber with a specific ring designed to deform the case neck upon firing. This action slows the bolt's rearward travel, effectively preventing bolt bounce during automatic fire and contributing to its unique ejection pattern.

What are some notable features of the Stgw.57 / PE57?

Key features include a complex roller-delayed blowback action, a fluted chamber with a bolt bounce reduction ring, a 24-round magazine, a folding bipod, grenade launching capabilities, and an intricate sighting system comparable to a Swiss watch.

How does the Stgw.57 / PE57 differ from the HK91 in terms of ejection?

Unlike the HK91, the PE57 exhibits a very soft ejection pattern, ejecting spent cases head/base first rather than neck first. This was a specific Swiss design choice intended to protect neighboring soldiers firing in formation.

Related News

All News →

More Gunsmithing & DIY Videos You Might Like

More from Military Arms Channel

View all →