What does it mean when a firearm operates from an open or closed bolt? This article explains how open-bolt and closed-bolt systems work, their advantages and disadvantages, and why most modern submachine guns and pistol-caliber carbines (PCCs) are designed to fire from a closed bolt.

The 9mm Luger, also known as the 9×19mm Parabellum, has been one of the world’s most widely used handgun cartridges for more than a century. Since its introduction at the turn of the 20th century, it has seen service through two world wars, become the NATO standard, and earned a lasting place among military personnel, law enforcement officers, and civilian shooters alike. How did the legendary “Luger” come to be, and what made it the most popular handgun cartridge in the world?

PCC carbines have seen a massive rise in popularity in recent years among competitive shooters, tactical firearms enthusiasts and everyday gun owners alike. They offer lower training costs, minimal recoil and extensive customization options, making them suitable for everything from sport shooting and home defense to casual range use. In this article, we take a closer look at the main advantages of PCC platforms, the differences between individual operating systems and what to consider when choosing the right setup.