>>64204458
That cycle of operations film is how I first learned how guns worked, I was gonna mention it.
Anyways, others in the thread have already recommended most of these, but here are some of my favorite channels:
Paul Harrel: Very down to earth practical application of firearms knowledge to real life situations
Forgotten Weapons: Videos about historically significant firearms and firearm-related concepts, often disassembles the weapon and explains how it operates
Hoffman Tactical: Homemade firearms and experimental weapon systems
Brandon Herrera: Gun memes, culture, and politics
Garand Thumb: A mix of weapon reviews and fun, LARP-y content