Homebuild History – Practical Scrap Metal Small Arms

Welcome to Homebuild History, the part of 3D Gun Builder’s website where we focus on the history of some of the most iconic homebuilt firearms, their contributions to the world, and most importantly, how YOU AT HOME can get your hands on these classic arms and armaments!

What’s the Story?

You may have seen the Practical Scrap Metal Small Arms series on occasion as a point of reference for homebuilt designs. That said, we’ve yet to take a dive into the sheer creative genius of the one, the only, Professor Parabellum (PPara). Join us this week as we examine the enigmatic designer’s work and watch how a simple scrap pistol started a whole brand.

homebuild history practical scrap metal small arms
Proper Pistoleros

Scrap metal pistols of various calibers and capabilities have been around since the pistol was introduced. The idea of having to scavenge for resources to make a capable firearm is old, but few people have ever actually given the general public the opportunity to engage in such a pastime. At least, until recently.

IMG 3134
A high-quality example of Professor Parabellum’s first pistol design, made by a man known as Clinton Westwood.

The first edition of Practical Scrap Metal Small Arms appeared years ago, showcasing a .sheet metal 25 ACP pistol. While unordinary and plain initially, a YouTube build of the gun by the pseudonymous Clinton Westwood made the design, to say the least, cool. By then, however, the enigmatic designer had moved on to other things.

Volume 2 and 3 of the series had already given the world a homebuilt MAC-11 and homebuilt Sten Mk 3 design. By volume 7 and 8, more of a focus had shifted towards creating unique small arms designs, like the derringers and the Bullet Hose submachine gun. Homebuilders around the world had begun to take notice and dipped their toes in the water of his designs.

A build of the Volume 14 break-barrel shotgun. Crude finish, but it works perfectly.
Arming the World

By the time Volume 20 had come along, Professor Parabellum’s designs were being globally proliferated. In Brazil, many derivatives of his MAC-11 and MAC-10 submachine guns were found by police in Minas Gerais. A Canadian man was arrested with a Sten and one of his pepperbox pistol designs.

At the same time, even more innovative designs sprung into being, such as fully automatic combat shotguns and the Improvised Special Purpose Submachine Gun. A serious contender for the least parts in any fully automatic gun, the design contained less than a dozen pieces.

The quintessential Improvised Special Purpose SMG. One of the simplest guns ever made.

Eventually, Professor Parabellum’s series would transition into the realm of hybrid designs, combining his own or integrated printed work with his tubes and sheet metal. While not necessarily part of the Practical Scrap Metal Small Arms series, these designs have been interesting takes on printing guns. Few people choose to combine traditional homebuilding with modern printed designs the way PPara does.

Recently, the enigmatic designer has gone even bigger than his prior work with the creation of landmines and copies of IRA mortar technology. At this point, PPara’s inventory spans practically everything small arms and beyond. PPara even developed bomblets based on the VOG-17 grenade. The designs are direct copies of those used in Ukraine by both sides of the conflict.

Who Even Is He?

The obvious question about Professor Parabellum is “who is this guy?” He’s incredibly difficult to get in contact with – personally, I’ve lost contact with him twice. The only thing anyone knows about him is he’s from southeast Asia, which, as everyone knows, is an incredibly small part of the world with very few people living in it.

PPara’s designs are more international than the United Nations. He’s developed weapons based off Bulgarian, American, Irish, Yugoslavian, Chechnyan, British, Ukrainian, Russian, and even North Korean technology. How he both knows how these things work and perfectly replicates them is a miracle in and of itself.

A fully CADed Provisional IRA Mk 10-1 mortar system. Someone get this man a pint of cider.

Professor Parabellum has more than proven himself as a weapons designer. By any means, he should be employed at a major military manufacturer. The man deserves a six figure career, maybe a yacht and a winery off the slopes of Vesuvius. If anyone manages to bring him to the United States and employs him, he will do wonders for their company.

Good luck to you, man, and may your dreams of turning this into a career come true.

How do I make it?

Well, that depends where you want to start. One thing to note when building* any of the Practical Scrap Metal Small Arms series is legality. Many of these designs PPara are be restricted or illegal under US law. Any machine guns can only legally be built by an FFL with an SOT, and some of his other designs would be AOWs needing a tax stamp.

PPara’s files are everywhere. Even archive.org has multiple copies. The Gatalog realistically has the most complete and up to date collection. Be aware, though: these designs are not as simple as printing a frame and assembling some prefabricated pieces. You will be turning raw materials into finished components, and it will take a lot more effort than typical homebuilds.

As always, tune in next week for more Homebuild History! Stay safe and build on!

*Legally, of course. Laws don’t stop you from building this, but we at 3DGunBuilder encourage readers to follow all legal guidelines. If you can’t make this in your state or country, please don’t try to. Just remember that this is here for educational and research purposes only.

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