DIY Sten Gun

@Tenacious221 They were designed to be simple to manufacture using standard firearms factory equipment.
Actually, functional firearms can be made without any power tools -- after all, firearms were in regular use BEFORE power tools were invented. But that doesn't mean that a safe, fully functional, firearm using modern ammunition can be tossed together out of random scrap using your trusty pocket knife and a roll of duct tape, by Larry, Daryl, and his other brother Daryl.
Yes, someone with the right skills, patience, and the right hand tools could create a reasonable copy of many of the simpler modern firearms -- but such people are not the audience that are buying these books.

@Xaun Loc ... but these PDFs are entirely free.

An angle grinder, welder, drill, hacksaw and files are hardly akin to duct tape... You don't know of Luty, do you son?

@Xaun Loc We're not building something that's intended to be "safe" or "long lived"; we're making something functional enough to use against an enemy that has a manufactured weapon, then take his. Trade a garage sten for a DHS UMP .40 or M4, then go to town. But that garage sten will get you to the UMP .40 a lot faster than a pointed stick.

@Xaun Loc You don't know much about your firearms history, do you?

The SMGs like the Sten and the Leningrad version of the PPsH were designed to be simple enough to manufacture that they could be made by companies (in the UK) or just people (in places like Leningrad) with standard machining equipment but without "standard firearms factory equipment" (whatever the heck that is) and little to no experience in the manufacture of firearms themselves.

BTW, what exactly IS this "standard firearms factory equipment" you refer to anyway? About the only thing I can think of off the top of my head would be a specialized boring machine for cutting the internal rifling in the barrels. Anything else in a WW2-era factory making Sten guns or even just some of the parts for them was pretty much standard metal fabricating equipment.

Do you mean CNC machines and so forth? Because you certainly do need that type of equipment nowadays to produce firearms on a commercial scale at a viable price point. But you certainly DON'T need it just to build a single gun over time for personal use or even a handful for yourself and friends.

@screwtape2713 . Well, screwy, apparently I know more about firearms and firearms history than you will ever learn (if you do ever learn anything). The point I made was that the Sten was never designed to be thrown together at home by bubba with an electric drill and a grinder -- as even you realize all the real firearms we have been discussing have rifled barrels and the majority of them have chambers bored accurately enough for the round to headspace on the case mouth. These so-called instruction manuals are mostly sold to drooling idiots at gun shows and prepper events -- the manuals claim that the complete firearm can be built by anyone with the kind of simple tools found in a typical workshop or garage. The say "drill" but the reality for any chance of real success in copying even a simple modern firearm (such as the Sten) is a drill press. For most of the firearms that are typically described, a lathe and/or milling machine may not be absolutely essential, but make the difference between a rational project and a pile of junk that gets tossed after sitting on the workbench for a year or two. Likewise welding equipment may not be absolutely essential, but trying to align and attach a magazine well to the receiver tube of a Sten is no picnic with a vice and some epoxy.
There are lots of one-time-use firearms that really can be built without major metalworking tools, but those aren't as sexy as a Genuine Imitation Sten SubMACHINEGUN.
Building a semiauto or full auto firearm that will safely feed and fire modern ammunition requires precision that might be achieved by skilled artisans using "simple" tools and a lifetime of experience -- but not by the usual market for these manuals working on their first project.
The charlatans pushing these Build Yourself A ______ Machine Gun manuals originally fell into two categories: The crooks conning people into just buying the manuals and the bigger crooks conning people into buying the manuals so that they will come back to buy the parts kit before still failing to build a working firearm. Most of that second category have quit as the supply of cheap parts kits dried up, but every gun show will have at least a few vendors trying to sell Xeroxed or QuikPrinted copies of these silly manuals.

@Xaun Loc I just logged onto this website again and found the continuation of the discussion.

Ignoring your completely unnecessary insults ("screwy"??), I think the difference between us might possibly be the type of environment in which we live. I'm not sure where you live or what type of people you commonly meet, but I grew up and still live in an area of my country that relies heavily upon agriculture for its economy.

That's a fancy way of saying that I grew up and live around a whole bunch of farmers and farmkids.

Some of them have taken formal professional training and certification as welders, millwrights or heavy mechanics, but many just learned from older relatives and by doing. And again, some have fairly complete metal shops on their farms or in their garages in town - often assembled over a period of many years - but many of them actually have access to hand and power tools at about the minimum level of that called for in these plans.

Based on your comments, I think you would be absolutely stunned to see the sort of stuff those guys can make when they put their minds to it - using just junkyard scrap, fairly simple tools and their imaginations. I can think of at least a couple dozen guys just off the top of my head who could knock one of those toys out with no problem at all, if they wanted to.

Of course, my personal view on the practicality of those DIY Sten Gun plans might also be partly affected by the fact that I KNOW it's doable, because I have personally SEEN it done.

In fact, on one of those farms I just mentioned, which is located located somewhere within my home province, on a lovely fall afternoon that occurred sometime between August and October on a year sometime between 1990 and now (and for obvious reasons, I am never ever going to be more specific than that), I spent a few hours visiting one of these types. And in the course of that afternoon, it came about that I had the opportunity not only to view and handle such a DIY SMG but to testfire it on the back 40. And you know what? It worked just fine...

Oh yes, and that particular guy was one of the ones who was NOT a professionally trained millwright and did NOT have access to a complete metal shop.

Of course, the last part of your comment, you seem to "assume" for some peculiar reason that these manuals are DESIGNED for an urban 8th-grader who has never held a simple hammer before in his life and is going to pick the DIY Sten Gun as his very first shop project... Personally, I'm not sure where you came up with that assumption, because I didn't see anything in the plans myself that specified "designed to be usable by a fumble-fingered idiot with no experience whatsoever in ever building anything"...

@screwtape2713 . You really cannot comprehend the difference between what can be done by a person with training (formal or informal) and a fairly complete machine shop (typical of many rural communities) versus what the untrained urban wannabe can do with regular hand tools.