Unique Firearm Inventions of WWII

Unique Firearm Inventions of WWII

The period surrounding WWII saw an abundance of creative inventions. This was especially true in the area of firearms. It was the first war to see the use of sub-machine guns, such as the Sten Gun, the Thompson, and the unusual looking Owen from Australia. However, these guns were hardly the most unique additions to the battlefield, and although they elevated the small arms firepower, they didn’t significantly decide the battle in favor of one side or the other. So it became the paramount task for all of the nations involved in the conflict to keep searching for something that could make their army superior. 

Some inventions were clandestine, while others were large and hard to keep hidden. There was creativity and ingenuity abounds on both sides of the conflict. Allied and Axis forces were placing their finest minds to the task of developing the next game changing, or should we say war changing, invention.

Ultimately, there were so many ideas pursued that it would amount to far more than what we could cover here, so we chose just a few of these odd inventions that were unique in both their appearance and purpose.

The first small item that we would like to discuss is a pistol that was built for only a very brief period during WWII. Not many people outside of gun collectors and other interested parties knew anything about it, until much later when it gained the interest of those looking to recreate it. This gun was a rustic and impractical weapon that was built for one very specific purpose in mind.

The Liberator Pistol was a cheaply made, pot metal gun that was contracted out to and manufactured by the Guide Lamp Division of General Motors. The task that the Allied Armies had in mind for these cheaply made pistols was to have them air dropped across the European countryside, in the hopes that they could be used by civilians and resistance fighters to take out Nazi soldiers. This in theory would allow them to obtain the more powerful weapons being carried by their targets. They also believed that just the knowledge that an assassin’s pistol existed and could be in the hands of civilians would curtail the bold confidence of the German troops.

The Liberator was comprised of 23 crude parts that could be completely assembled by factory workers in a matter of just a few moments. It was once said that it is the only gun in history that could be built faster than it could be reloaded. 

The concept for the Liberator was first presented by the Polish Military Attaché, but it was the Americans that would ultimately pursue the idea. Credit for the design of this simple pistol goes to a General Motors designer named George Hyde. 

At the time, the project was a secret and was called the “Flare Projector 45”, hence the FP-45 designation. The deception with the name was to keep its true purpose hidden from anyone that may discover that the auto manufacturer was building weapons.

The pistol was constructed from sheet metal and had a cast zinc cocking knob, which also contained the firing pin. The barrel was spot welded to the frame and the grip was left hollow to accommodate ten rounds of .45 ACP ammunition. Once assembled, the pistol was packed into a paraffin-coated cardboard box along with a wooden dowel that was to be used as an extractor for the single shot pistol. It also included an instruction sheet that was created in the form of a comic strip, so that anyone no matter what language they spoke would be able to understand. The total cost for the completed pistol, ammunition, wooden dowel, and storage box was $2.10.


For six months in 1942 the factory ran around the clock with 300 workers assembling these crude guns. An unprecedented one million Liberators rolled off the line in that time.

However, once the project was completed it was realized that air dropping a million pistols into occupied territories was easier said than done. Most of the guns were handed over to the OSS (today known as the CIA), with only about 25,000 actually being air dropped by the British to French resistance fighters. Some of the pistols also found their way to Greek resistance fighters and about 100,000 were sent to China and the Philippines. 

But sadly, many of the guns were never used at all and were simply disposed of to free up space. They were either destroyed or dumped into various seas around the world.

The life span of the Liberator was estimated to be between 25 and 50 rounds. So, many of the pistols that did actually get fired began to fall apart rather quickly. The welds would break free and parts would warp or bend, so they were truly just designed for the single task, and were otherwise disposable. With most of the guns falling to one of these fates, it is easy to see why a functioning sample would be a highly sought after addition for anyone attempting to complete a WWII era weapons collection.

Next up: is a bizarre looking add-on device that did make it into combat and much to our surprise can still occasionally be found in its original form on online auction sites.

The Germans may just have invested more time and energy into technological advancements than perhaps any of the other countries involved in the war. This was especially true when the outcome appeared bleak for Hitler’s forces. They aggressively sought out any idea that could provide them an edge over the enemy.  So, in Germany many strange and unusual things began to take shape.

Some were done on a grand scale like the Gustav Gun, which stood four stories tall and measured 155’ long, and weighed 1,350 tons. The Gustav had a 98’ barrel and fired a projectile weighing 10,000 lbs. This gun was completely impractical and of course was easily located and destroyed by Allied Forces. 

Some other German inventions weren’t quite so massive, but still unusual in their own right. One of these odd looking things was the Krummlauf (curved barrel) attachment. The first efforts to create this contraption were tried using a 20mm tube attached to an 8mm caliber rifle, but this was found to be clumsy and inefficient. The bullet could not be aimed and it would simply tumble uncontrollably through the air. 

However, they did quickly discover that using a smaller projectile and tightly rifled barrel would get them closer to the desired result. So they developed the Krummlauf to work with their 7.92 caliber rifles - the Maschinenpistole 43 (MP43) and the Sturmgeschütz 44 (STG-44). 

Even with these smaller rifles, the design was not perfect and the projectile would fragment as it traveled through the bend of the attachment, creating a shotgun-like effect. But this was deemed to be acceptable, since the guns were going to be primarily used for close range and mainly to keep enemy soldiers from climbing on and disabling German tanks. 

The Krummlauf featured a periscope sight with a mirror that allowed the shooter to see around obstacles. They built 30º barrel (known as Vorsatz-J) for foot soldier use and a 90º barrel (Vorsatz-P) that was used for vehicle protection.

The Krummlauf device attached directly to the barrel, locking over the front sight of the rifle. It was then secured in place with an L-shaped bolt. The rifling in the device began after a small bored out section, which allowed the bullet to jump from the rifle barrel to the Krummlauf and re-center itself. Gas ports were added to relieve some of the pressure, but these proved to have little effect in preserving the projectile’s integrity.

Just like the Liberator, the Krummlauf had a short life span. Although, they would last two to three times longer than the disposable pistol, the rifles fitted with the Krummlauf device were large and unbalanced and offered absolutely no advantage over a standard rifle during man to man combat.

As incredible as it seems, the idea of affixing a curved barrel to a rifle and fitting it with a periscope was not first envisioned during WWII. There were actually attempts made to use this bizarre technology as early as WWI. The troops were bogged down in trench warfare and someone thought to consider a curved barrel to fire from inside the trench. However, it didn’t amount to much of an advantage, and the Krummlauf was far more advanced than those early attempts. 

After the war this idea continued to be researched and reinvented and copies were made by the Russians, Americans, and the Japanese. None of them ever saw any real production or wide spread use. 

Today there is a much more logical and advanced weapon used to shoot around obstacles. This device is known as the CornerShot, which is an apparatus fitted with a GLOCK pistol, a high-resolution camera, and a 2.5” color LCD monitor. The CornerShot can also be equipped with a grenade launcher, flashlights, and other tactical gear. So what originally appeared to be a weird and even dangerous idea, actually lead to the development of a another pretty sophisticated device.

The final weapon in our discussion was designed for much the same purpose as the Liberator. However, its quality is far superior and it has a much greater chance of standing the test of time.

Have you ever wondered where they came up with all of those cool secret weapons for the James Bond films? Well it would seem that the British may have always had a knack for developing such intriguing gadgets and their fictional top secret laboratory that is seen in the films may just have been loosely based on some real life inventors. 

Way back in 1943, the designers at Station IX of the S.O.E. (Special Operations Executive) were tasked with building top-secret weapons. It was there that they came up with this odd looking, but effective assassin’s pistol. 

Major Hugh Reeves was the mastermind behind this silent and deadly Welrod Pistol and BSA (Birmingham Small Arms Company) is believed to be the original manufacturer, although they do not openly take credit for it.

Much like the Liberator, the Welrod was intended to be air dropped to resistance troops during the war. The Welrod is a magazine-fed, bolt action pistol. The magazine that it uses is a modified 8-round Colt 1903 Pocket Hammerless box magazine that is covered with a very hard rubber known as ebonite. The magazine doubles as the grip when installed. This allows the weapon to be easily disassembled, and alters its appearance to look more like a bicycle pump than a gun.

A knurled knob at the rear of the tube operates the bolt. Inside the tube, just beyond the bolt face is a 3.25” barrel, followed by an expansion chamber with a series of metal baffles and rubber wipes (discs), which acts as the suppressor and creates the silencer effect.

The MKI Welrod model used the .32 ACP caliber, which contains only a small amount of powder charge and is not terribly loud in the first place, so it worked out perfectly for this Hollywood quiet assassin’s pistol. The MKII Welrod was basically identical but used the 9x19 Parabellum ammunition.

The Welrod was found to be such a promising tool that it never really went away. It is still used by certain agencies in allied countries for specific reasons even today. (Yeah that statement was vague on purpose.)

There is also a modern pistol that is closely based on the original design known as the VP9 (Veterinary Pistol 9mm). The VP9 is produced by a Swedish company named Brügger & Thomet. This pistol comes with two interchangeable suppressors that can be maintained by replacing the rubber washers, which is something that couldn’t be done with the original pistol. The VP9 is meant for the purpose of humanely putting down sick or wounded animals, or at least that is the claim made by the manufacturer. (Insert wink here.)

The few weapons that we discussed here really only scratch the surface of what came out of the arms race of WWII. The innovations and ideas during that period were many and helped advance certain technological understandings worldwide. They definitely changed how nations approached war and opened the door of possibilities for future inventors. 

As always we will suggest to our readers who possess a genuine interest in the topic, to do further research and discover for yourself just how embedded firearms have been in all aspects of the World’s history.