A Beautiful Factory Semiauto SIG MKPO

Published on February 24, 2025
Duration: 14:54

This guide details the field stripping procedure for the SIG MKPO, a rare semi-automatic variant of a 1930s Swiss submachine gun. It covers removing the end cap, bolt carrier, bolt, and recoil spring. The video emphasizes the high-quality Swiss machining and unique safety interlocks. Instruction is provided by Ian McCollum, a recognized expert in historical firearms.

Quick Summary

The SIG MKPO is a rare 1930s Swiss semi-automatic submachine gun variant, featuring a tilting bolt, folding magazine, and top ejection. Developed by Gotthard End and Jacob Gaetzi, only 1,228 units of all MK variants were produced. Notable users included the Vatican's Swiss Guard and the Finnish military.

Chapters

  1. 00:00Introduction to the SIG MKPO
  2. 00:55Model Variants and Calibers
  3. 02:45Mechanical Features: Folding Magazine
  4. 05:22Operating System Analysis
  5. 07:04Disassembly and Internal Components
  6. 13:01Production History and Users

Frequently Asked Questions

What is the SIG MKPO?

The SIG MKPO is a rare, factory semi-automatic version of a submachine gun developed by SIG in the 1930s. It was designed by Gotthard End and Jacob Gaetzi and features a tilting bolt mechanism and a folding magazine.

What calibers were SIG MK series firearms chambered in?

SIG MK series firearms were chambered in various pistol cartridges, including 7.65mm Luger, 9mm Luger, 7.63mm Mauser, and 9mm Mauser. The specific example shown is in 7.65mm Parabellum.

How many SIG MK variants were produced?

A total of 1,228 units across all SIG MK variants (MKM, MKP, MKPO, MKMS, MKPS) were produced between 1933 and 1941. Notable users included the Vatican's Swiss Guard and the Finnish military.

What are some unique features of the SIG MKPO?

The SIG MKPO features a folding magazine that stows into the forend, a tilting bolt system, and a unique safety interlock that prevents firing if the receiver end cap is not fully secured. It also has a top-ejecting receiver.

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