How the ROF ejector works

This guide details the process of tuning an AR-9 style platform, specifically a Daniel Defense PCC, to reliably function with the ARC Fire trigger system. It covers essential modifications like dremeling the bolt carrier, selecting appropriate buffer and spring combinations, and testing with subsonic ammunition. The expert-level insights highlight the trial-and-error involved in achieving optimal performance on a blowback system.

This guide covers the basic disassembly, cleaning, and reassembly of the Beretta PMX, based on expert instruction. It highlights the importance of maintaining the firearm to NATO specifications for reliability. The video features detailed technical explanations and hands-on demonstrations, emphasizing the PMX's evolution from earlier designs and its modern features.

This guide details the disassembly and reassembly of three experimental lightweight Lanchester SMG prototypes, as demonstrated by Ian McCollum. It covers the unique features of each model, including reversed barrels, modified bolt designs, and folding stocks. The process involves removing the end cap, bolt, and mainspring, with specific attention to the distinct modifications of each prototype. This information is presented with high authority from an expert with access to museum collections.

This guide details the field stripping process for the Marlin/United Defense UD-42 submachine gun, as demonstrated by Ian McCollum. It covers the basic steps to separate the major components for cleaning and maintenance. The process is described as straightforward, involving a single disassembly lever.

This video details a failed attempt at stamping a firearm component using a 120-ton hydraulic press. Mark Serbu, owner of Serbu Firearms, highlights the critical importance of precise material alignment and die design in sheet metal stamping. The demonstration showcases common pitfalls, such as misalignment leading to skewed parts, and the challenges of achieving complex bends with simple dies. Serbu emphasizes that learning from failures is integral to the engineering process.

This guide, presented by C.J. of AT3 Tactical, offers an expert overview of building or acquiring a 9mm AR-style rifle (AR9). It details the unique components differentiating AR9s from AR15s, discusses historical context, explores magazine and operating system choices, and outlines the paths to AR9 ownership: conversion, purchase, or custom build. The instruction emphasizes understanding the specific parts required for reliable function, particularly concerning Last Round Bolt Hold Open (LRBHO) and blowback systems.

This guide details the complex process of converting a lathe into a 12-barrel blank-firing gun, as demonstrated by Mark Serbu. It highlights the critical engineering challenges, including precise alignment, CNC control, and the application of PID theory to overcome firing inconsistencies. The project emphasizes safety and legal considerations, focusing on blank ammunition to avoid machine gun manufacturing regulations.

This video demonstrates how to rifle a barrel in a home shop using basic tools, bypassing expensive CNC equipment. It covers material preparation, precise drilling and reaming, and the critical process of pushing a rifling button. While a DIY approach is shown to be possible, the video highlights the significant difference in quality and precision achievable with professional CNC machining.

This video provides an expert-level analysis of a catastrophic failure of the Serbu RN-50 rifle, presented by the firearm's designer, Mark Serbu. The examination focuses on the severe damage to the receiver, breech cap, and barrel assembly, offering insights into potential failure points and the effects of extreme forces. The analysis also touches upon the ammunition used, specifically SLAP rounds, and their potential role in the incident.

Mark Serbu, a gun designer, addresses the RN-50 blow-up incident involving Scott from Kentucky Ballistics. Serbu reassures customers that the RN-50 is a safe design, attributing the incident to a counterfeit and faulty ammunition round. He emphasizes the importance of sourcing ammunition carefully and highlights the rifle's extensive safe operational history.