Hi guys, thanks for tuning in to another video on ForgottenWeapons.com.
I'm Ian McCollum, and I am here today at
the Dutch National Military Museum.
We're taking a look at some of the guns
in their extensive firearms collection,
including this very unusual
and very cool French submachine gun.
What makes this unusual is that it has
a clock-spring type mainspring.
And when you fire it this whole thing spins in circles
back and forth. Really interesting and really unusual.
Now this was developed after World War Two.
The designer was a Frenchman by the name of Louis Debuit.
And ... I should say the designation of the thing is the MGD PM-9.
So PM-9 is Machine Pistol, "Pistolet Mitrailleur", 9mm, a submachine gun.
And then MGD stands for the two guys who ran the company that manufactured them and the designer.
So "M" and "G" were "Merlin et Gerin" and the designer was Debuit, Louis Debuit.
So what he was trying to do was design a submachine gun for the French police.
He wanted something that would be extremely easily concealed.
So that you could have officers who were armed, but not alarm the public,
or not make it real obvious that they were all armed.
So this thing folds up ... into a very compact package.
This is even ... smaller than the Hotchkiss Universal.
And then it can be deployed very quickly
into what is a pretty much functional submachine gun.
It's a little crude in the handling, kind of like a Sten,
but it gives you the opportunity to have a very compact gun.
Debuit originally designed this gun for the 7.65x20 French Long pistol cartridge.
That's the cartridge they used in the 1935 pistols and in the MAS 38 submachine guns.
And that variation of the gun actually used MAS 38 submachine gun magazines.
Make sense, that's the only large magazine out there for this type of gun in that calibre.
However, he apparently realised quite quickly that no one was interested
in another submachine gun in 7.65 French.
That cartridge was obsolete right at the beginning of World War Two,
much less at the end of World War Two. By that point everyone was using 9mm.
The French would move to 9mm for their military submachine guns by the late 1940s.
So by the time this was actually in production the French military was using the ... MAT 49.
And so Debuit redesigned this to use 9mm,
and interestingly he chose to use MP40 magazines to do so.
Of course late 1940s ... in France there are MP40 magazines easily available all over the place.
This is an interesting early example of someone designing a commercial gun
based on a readily accessible, available, existing magazine.
Something that we see today, and we really like often today in the civilian market.
When someone comes out with a new gun, you know what, use a magazine that's cheap
and readily available instead of forcing us to go buy some proprietary thing.
Well, that's exactly what they did here.
As for the rest of the gun, it's actually pretty clever and interesting on the inside.
It's worth noting that very few people have ever copied this design.
So let's take this apart and take a look at how it works, and why it hasn't taken off.
Controls on this are very simple and easy to work with.
The stock doesn't have any sort of solid lock.
What happens is when you bend it here, it pulls these two bars out of these little recesses.
So there's a little bit of spring tension always holding the stock [locked].
But in order to fold it, you just push it to the side.
On this side we have a safety selector,
which will only go into the safe position if the gun is cocked.
In order to do that, we're going to take the handle and rotate it 180 degrees around.
(While it grabs the gloves.) Now the gun is cocked.
So now I can move the selector into the safe position if I want to.
There is another safety on this, and that is rotating this another 90 degrees.
See the hole there, I can push this button on the bolt handle and lock this plunger into that hole.
On a rotary gun like this, that's the equivalent of the extra notch
on a typical submachine gun like an MP40.
Where you would pull the bolt back and rotate it up into the locking notch
to securely lock it in place, that's what we've done here.
So now I can pull the trigger all I want, it does release the sear,
but the spring and the bolt are held in place and can't go anywhere.
And in order to release that, we just push the handle forward and it disconnects.
This fires from an open bolt, but it does have a floating firing pin,
we'll take a look at that in just a moment.
And what happens is when you fire, the bolt is going to come forward, chamber a round,
fire it, and then of course recoil backwards.
Which is going to cause this clockwork spring to rotate, there we go.
And at this point the bolt catches on the sear and locks in place.
But the spring can continue to cycle backwards,
that acts as the over travel for the bolt.
So on a tube receiver type submachine gun you need to have a sufficient space behind the magazine
for the bolt to slow down, come to a stop, and then start moving forward again.
On the PM-9 here ... you're doing that rotationally instead.
So the bolt only has to come back this far to feed,
but then it's going to travel all the way through to here to decelerate.
And by allowing it to decelerate that way you don't need a heavy buffer spring
at the end of the bolt's travel, and it's going to also reduce the rate of fire of the gun.
We have two buttons down here, one on each side.
The button on this side allows us to unlock the magazine well to fold it forward.
And the button on this side allows us to remove the magazine.
And this is a (... it's written on one side there, there we go),
this is a standard MP 38/40 magazine, so 32 rounds, 9x19 Parabellum.
There is a two-position rear flip sight.
So two different apertures for different ranges, I believe that's 50 metres and 100 metres.
And something that I've noticed on so many French submachine guns,
these sights are both very small and they're very low down on the gun.
You really have to cram your face down on the stock in order to get a sight picture.
And we also have a very stereotypically French front sight.
It's a fairly wide square front sight that has this notch cut in the centre of it.
And the theory is the wide front sight gives you a quick acquisition sight picture,
and that centre notch gathers a little bit of light and it can be used for precision shooting.
So the French developed this during World War One, and they use this style of sights on
... the Lebels, the Berthiers, the 1917 self loaders,
the ... MAS 38 submachine guns, this was a very standard style.
Alright, now to take this apart we have this button,
checkered on the front so you can get a grip on it.
And what you do is (actually I'm going to drop the bolt first,
you can kind of do this in any position, but it's a little weird),
we pull this back and then this whole panel lifts up and off of the gun.
Maybe.
I'll get it here. There we go!
Thank you.
Alright, so one easy little button just like that.
And this is our whole mainspring ... assembly really.
And then this big round lug runs in this track in the bolt.
So the bolt is simply going to cycle back and forth like this
because it has a lug in it that is rotating.
So this is the position everything starts in.
And then as this rotates through the first 180 degrees,
it's going to pull the bolt back over the sear to here.
Then we'll have the handle at this position,
and it's going to continue to rotate down through this area.
And we have this track where it can come out, come back down through here,
and then cycle back up. So that's how the recoil system works.
The firing pin is free floating, and you can see it right back there.
So when I push on that, the firing pin comes forwards.
This lug on the bolt is going to hit that firing pin and cause it to protrude
just like that.
When everything is aligned, when the bolt is fully forward and the handle's forward,
then it's fully closed and it automatically fires. And then starts the sequence again.
Typically in a submachine gun we would have the sear catching on the bolt.
In this case the sear actually catches on ... the recoil mechanism.
So this hook, right here, is what catches on our sear, right there.
And we have a flat spring that provides tension to the trigger and sear.
Fortunately when this was designed, Debuit had the presence of mind to make this a sealed unit.
So the spring remains wound inside here, and it is a clock-type spring wound up.
And to take it off what you would do is rotate this lock pin 90 degrees.
But there is no way I am doing that,
because I don't want to have to try and rewind that clock spring.
As long as you leave it assembled, when this handle moves that lug on the back moves along with it.
You'll also notice that there is a little square cutout right there,
that is a safety, so that when this is in the rearward position, ...
so ... when we have the bolt handle back here,
it would be coming back down into the bolt track.
And you want to make sure that you don't have the possibility
to have a cartridge carried in the front of the bolt
and then accidentally fire it while the gun is fully open.
That's why that cutout is there, so that this lug can't engage the firing pin
at the rear end of travel. Only at the front end of travel, right there.
One last neat little element is this plug in the bottom of the stock, which is a cleaning rod.
It's threaded in there, and it's going to take me a moment to unscrew.
There we have the complete cleaning rod, ... a slot in the front for a cleaning rag.
Why they made this a separate piece that's held together by the cleaning rod, I have no idea.
But they did for some reason.
Well, I'm really happy to have finally got a chance to take a look at one of these,
they are a very notable and unusual firearm because of this clockwork style of mechanism.
If you're interested in firearms like this, especially if you're interested in Dutch firearms,
make sure to stop by the Dutch ... National Military Museum if you ever have a chance to.
They have an excellent collection, it's a brand new building and really extremely well done.
If you like seeing this sort of thing on the internet
I would appreciate it if you'd consider taking a look at my Patreon account.
It is support from the folks there at a buck a month that makes it possible
for me to travel to places like the Netherlands, find these guns and bring them to you.
Thanks for watching.