Hi guys, thanks for tuning in to another video on ForgottenWeapons.com.
I'm Ian, and today I'm here at the Institute of Military Technology
taking a look at some of the really cool firearms,
experimental and unusual firearms in their reference collection.
And today we're taking a look at a SIG KE-7 light machine gun.
This is, well, it's made by SIG, it's Swiss in design and this was developed
potentially for Swiss military contracts, but it never got those.
So it ended up being sold on the international commercial market instead.
Now not a lot of people actually adopted this gun, but there were substantial numbers of them sold to China.
It was first introduced in 1929 and it was designed by two guys working at SIG,
a guy named Gotthard End, and a Hungarian designer named Pal Kiraly.
(Or I think something like that, that's how his name is spelled anyway.)
Now Kiraly shows up in a lot of other interesting guns that we have looked at in the past
and we'll look at in the future on this channel. So this is an interesting additional example of some of his work.
Now, this is similar in many ways to some of the SIG rifles from this period, the 1920s.
And it's got a lot of cool features, and the machining on it is just mind-blowingly intricate.
A couple things to start with. This is I believe a 50 round magazine, which is substantially longer than standard.
Normally these were issued, or sold, with 25 round magazines.
And this actually kind of gives you an idea of why large magazines weren't typically used on bottom-fed light machine guns.
Because this thing is simply too long. The reason we have this gun up on this
piece of plexiglass here is because the magazine high centres the gun on its bipod.
And that's the problem with large magazines on the bottom is they lift the gun really high up off the ground.
Anyway, a standard mag, 25 rounds, is about that long, which is much more practical.
Now this has a couple of interesting features to it. The trigger is a progressive trigger.
The gun fires from an open bolt, but if you pull the trigger about half way back
you'll fire fire single shots, and the gun will lock open after each shot.
If you pull the trigger all the way back, that fires in full-auto until you release the trigger.
And then one of the interesting features, with most ... open bolt guns, when the magazine is empty,
you know, you pull the trigger one last time and the bolt just goes kerchunk forward,
and fails to pick up a round because the mag's empty.
And then you replace the magazine and lock the bolt back, and you can fire again.
SIG actually built in a hold open device on this.
... Of course being an open bolt, it locks open whether the mag's empty or full.
But when the magazine's empty on this gun, which it is right now,
the trigger is actually disconnected, so
in order to reload it, all you have to do is replace the magazine. You don't need the extra step of charging the bolt again.
That's kind of a cool design. It's one of those things that kind of make sense,
but it adds an extra amount of complexity such that virtually nobody ever actually
introduced it into a firearm, except the Swiss in the 1920s.
This particular example is chambered for 8mm Mauser, which is typical. Most of the guns you'll find are,
because most of them were sold to China, and ... the Nationalist Chinese forces at the time used 8 Mauser as their standard cartridge.
However, SIG would be happy to sell this to you in pretty much any other rifle calibre that you wanted,
7mm, .30 calibre, 8mm.
You name it. Whatever you wanted, ... they'll tweak the gun to fit your cartridge.
Whatever magazine lengths you want they'll supply. And I'm sure they'd have been happy to accommodate
other requests like different styles of sights, or maybe sockets for anti-aircraft sights, that sort of thing.
Anyway, why don't we go ahead and take a look at the inside of this gun, because
there is nothing like machining from 1920s Switzerland.
So this is not actually marked KE-7 anywhere, but it is marked with
Swiss Industrial Society, Neuhausen, that is SIG. And serial number 5003 on this particular example.
Now what's interesting about this, which I will admit I only just
discovered while I was setting up to do this part of the video,
is that this is not a Chinese contract gun. This is actually an Ethiopian contract gun.
You can see right here, it's a very faint marking, a very shallow marking, but that is the Ethiopian Lion of Judah.
Ethiopia purchased a batch of ZH-29 rifles, which you will also find marked with this exact same lion crest.
Still in 8mm Mauser, as with the Chinese guns.
Not a whole lot in the way of controls. We have our mag catch here, which operates just like you'd expect.
Trigger, which I mentioned is a progressive trigger, so a partial pull, in fact I can demonstrate that.
In order to cycle the bolt you have to push the centre button down to disconnect the charging handle.
However, the bolt is currently locked back. So if I have it on the fire position, and if I pull just slightly,
bolt goes forward (it does pop open the ejection cover). If I hold the trigger there and cycle the bolt,
you'll notice it locks back.
And I can fire it a second time.
And if I hold the trigger all the way to the rear,
it's going to fire, and then
it continues to fire
until I release the trigger. So that's how the progressive trigger works.
I mentioned it has a trigger disconnect when the magazine is empty.
You can see it's still on fire, doesn't do anything, because I have an empty magazine in the gun.
Now our safe selector is there in front, that locks the trigger completely.
It also prevents you from cycling the bolt back.
The charging handle hits this pin.
You can see that there's a notch cut in that pin, and when the gun is on safe
the charging handle hits it and can't go.
But when I put the gun into the fire position, now that notch is lined up and allows the charging handle to go past.
That is an important element for
an open bolt firearm,
because one of the potential risks of an open bolt gun
is that if you have a loaded magazine in the gun and the bolt forward,
if you pull the bolt handle back, you can get it to a point where it is, say right here,
far enough back to pick a round up from the magazine,
but it's not far enough back to have hit the sear and be locked open.
If you catch the bolt handle on something with an open bolt gun like this, pull the handle back to this point, and then
release it, the gun will strip a round off and it will slam fire in an unintentional manner.
So that's something you want to avoid. And the safety selector on this does that
successfully by preventing you from pulling the bolt far enough back to strip a round.
You can only come this far back, not far enough to pick up anything from the magazine
Alright, anyway, the third position is all the way back, and that is disassembly.
Our first step of disassembly is going to be removing the front end of the gun,
the barrel shroud, the bipod, and the front handguard.
We're going to do that by lifting this lever up, and then I can rotate,
(... I should ... lock the bolt open).
(There we go.) Now I can rotate this
(... there we go) that rotates 90 degrees, and
I now have
two halves of a KE-7.
So this is our barrel shroud and our barrel.
I can pull the barrel out as well.
Now the literature says this has a quick change barrel, I would argue that that's really not the case,
it has a fairly easily replaceable barrel, but you're not doing this in the middle of a firefight.
And certainly there is no way to easily remove a hot barrel
... I guess you could, but this is not a combat changeable barrel. This is just an easily replaced barrel.
Now to disassemble the rear half of the gun, we're going to move the selector lever all the way back here,
this is the disassembly position.
Actually, first I'm going to go ahead and
relieve tension on the bolt. Now pull the selector lever over,
pull it out of the gun,
like that. And then
the ... top of the receiver is actually pivoting around this pin, and we can pop it off.
There we go.
Now this rotates all the way out and comes off of the top half.
So the top part of the receiver is basically just a housing. There's not a lot going on here, the real meat is in the bottom.
There's a lot of, "Holy cow, what is that?" going on with this thing.
We'll explain this in just a moment, first I'm going to pull the mainspring off.
There we go. Take that out, mainspring and it's guide rod.
And then we can lift off the bolt assembly, and now we just have the trigger assembly here.
I want to point out something about that progressive trigger first.
So here's our trigger,
this is the sear that holds the bolt back.
And then this is actually the back end where the mainspring attaches.
So the mainspring is acting as the sear spring, it's always pushing back like this.
And if I pull the trigger back just a little bit there's a disconnector.
You can see it drops and then snaps back up.
That's the semi-auto functionality. That drop is just long enough to release the bolt,
but then the sear pops back up in time to catch it on the recoil stroke.
If I pull the trigger all the way through,
the last stroke of the trigger pulls down all the way and holds the sear down.
So, semi, full.
This guy is just our trigger return spring to pull the trigger forward.
And then this up here is an accelerator.
So this is a short recoil gun, we'll look at this in just a moment.
First the bolt carrier assembly here and the bolt inside.
So, this comes down like this, and then we can pull it out the back.
The firing pin is pivoting on a little bar up there, so the firing pin can come out.
And then our ejector in this gun is actually also an extractor, which is pretty cool. So that also comes out.
It's not that often that you see really wildly asymmetrical firearms parts like this.
This is very, very much Swiss from the 1920s. It's hard to mistake that.
So let's look at how this actually works.
This is what we have when the gun is locked up. And what's happened is the bolt is locking into the barrel here.
So the barrel has this cutout in the top,
and that
connects with this bar on the bolt.
So that sits right in ...
(get this back together ...)
Alright.
That sits right there. And the important element here is we have locked the bolt and the barrel together.
So when you first fire the gun, these two are going to recoil back together.
So, once the bolt carrier starts moving back,
see that the bolt drops down this ledge,
and is then unlocked from the barrel, and able to travel backwards like that.
That's the locking stroke, that's the unlocking.
What does that is this little accelerator lever under here, this guy.
So this is held in the forward position by the bolt, like that.
The barrel is going to push backwards
on that lever.
That lever accelerates the bolt carrier backwards.
The barrel is also acting against this little spring, that spring interacts with this tab.
This flat surface right here, pushes on
this thing on the accelerator. That pushes the bolt carrier back.
Now there's an interesting thing that goes on here.
You can see that the bolt can travel a long ways
coming out of the bolt carrier. So what happens that allows pressure to drop while the gun is cycling.
So the accelerator pushes the bolt carrier back.
That unlocks the bolt, but it's not until these little lugs
hit the front of this cam track that the bolt is actually pulled backwards and starts to extract.
So during the cycle,
During the firing cycle here everything cycles back against a spring. We're unlocked,
we're unlocked right there,
but you've got all of this travel time for pressure to drop in the barrel
before the bolt starts to yank the case out.
That's going to improve extraction and make sure that you don't rip the rims off of cases.
So we're cycling back like this. The main spring is right here,
compressing, compressing, compressing, compressing. The bolt [carrier] stops there. It's going to recatch on
the sear, it's going to come to a complete stop right there.
But the bolt itself has residual inertia, and it's going to continue to travel back, pulling the empty case with it.
Until right there, when this left-side extractor
transforms into an ejector. You can see this little wedge or ledge in there.
Right there, that's going to start pushing the cartridge case forward. So the case had been like this,
and it's going to start to get tipped out the side of the gun as the bolt continues to come back.
That's full travel rearward of the bolt itself.
At this point the recoil spring takes over, and the whole thing starts to push forward.
As it goes forward that extractor is going to slide back into the bolt.
And somewhere right about here it's going to pick up a cartridge from the magazine,
cycle it back forward, forward, forward, and lock up with the barrel again.
It's a clever design, there's a lot of neat stuff going on here,
but I can only imagine how expensive this whole thing must have been.
The machining on this, like everything from the Swiss at this period, is glorious and runs like butter.
But that comes at a very literal monetary cost.
There you have it. One completely disassembled KE-7 light machine gun,
made by the Swiss at SIG and sold to the Ethiopian military in,
probably I think it was about 1932 that sale took place.
A fantastic, very cool gun.
Thank you for watching guys, I hope you enjoyed the video.
It's really cool to get a chance to look at these because, like all of the SIG products from this period,
there aren't a whole lot of them out there, and certainly very few accessible in the US.
So, thanks to the IMT for letting me pull this one off the wall and take it apart for you guys.
If you enjoy this sort of content, please do consider checking out my Patreon page.
It's support from the folks there at a buck a month that makes it possible for me to travel about,
find these guns and bring them to you guys.
And if you're interested in small arms research, definitely contact the IMT and arrange a visit.
They're not generally open to the public, but they are available by appointment.
Thanks for watching.