If you are interested in the history of small arms development, this series covers the massive transition period as black powder was abandoned and smokeless powder transformed repeating arms. What makes a good rifle, pistol, carbine, machine gun, combat shotgun, etc? Othias covers hsitory and context in depth, and Mae adds first-hand impressions by spending some range time with the firearm in question so she can give a more subjective take on how an infantryman might compare the attributes and different features.
World War I was a chaotic conflict with numerous countries involved, each with various arms for every branch of their respective militaries, and various theoretical doctrines had to face the cold reality of trench warfare. Some surprising designs made their way into the hands of rear echelon troops, and a few even faced combat. These videos have been produced since 2015, with 155 episodes at the time of this post. There is plenty to catch up on, and doubtless much more to come. Additionally, some of these weapons would see inter-war development and reappear again in World War II, or even just carry over as reserve inventory.
Depending on where you are in the world, you may have seen other examples here, but there are so many crazy ideas that were abandoned after war, or quickly superseded by better designs. I personally have limited experience with guns and designs from this era. I have fired modern renditions of World War I era Smith & Wesson .38 Special revolvers and 1911 auto-loaders. I have also had some trigger time with a couple Mauser-derived bolt-action rifles. What relics have you had a chance to fire?
If you're not on Hive yet, I invite you to join through PeakD. If you use my referral link, I'll even delegate some Hive Power to help you get started.