Hi guys, thanks for tuning in to another video on ForgottenWeapons.com.
I'm Ian McCollum, and I am here today at the
IRCGN collection, that is the central
firearms collection of the French Gendarmerie.
They have been gracious enough to give me
access today to come in and grab a couple of
cool guns to film for you guys.
So today we are taking a look at something that is
rather difficult to find out there
outside the French military, and that
is the AA-52 light machine gun, or general purpose machine gun.
This was developed as the result of a 1945 program
to modernise French military machine guns.
So the French had come out of World War Two
with the Châtellerault 24/29 as their light machine gun,
and the Hotchkiss 1914 still in service as their heavy machine gun.
And both of these were seen as being obsolete at this point and inadequate.
The Hotchkiss was just way too heavy of a gun, didn't have a high enough rate of fire,
the feed strip system was totally obsolete.
The Châtellerault was a much better gun, it was really a quite good light machine gun.
But the whole light machine gun concept was looking like it was becoming obsolete.
People saw the German universal machine gun concept in action in World War Two,
the MG 34 and the MG 42,
and came to the conclusion that this idea of a belt-fed gun
that could be fired off a bipod by a one or a two man crew as a light machine gun,
or put onto a heavy duty tripod, and supplied by a larger crew
with interchangeable barrels, and thus serve as a heavy machine gun.
People liked that concept, and so the French in 1945
instituted a program to come up with something like that.
Now three different organisations would ... do R&D towards this end.
One was the Saint-Étienne factory, one was the Châtellerault factory,
and one was AME, or the development group in Mulhouse.
These were the guys who in particular had
some German influence from the old Mauser R&D factory.
Well after a number of years, what came out of these three institutions was:
out of Saint-Étienne a gas-operated gun.
Out of Mulhouse, perhaps not surprisingly, essentially a modified version of the MG 42.
And out of Châtellerault a lever-delayed blowback gun.
Of these different developments, only Châtellerault's design
was found to be actually meeting all of the requirements, the criteria.
The standards for size, and weight, and rate of fire, and form factor, and reliability.
And so the Mulhouse and the Saint-Étienne guns were dropped,
and Châtellerault's gun was adopted as the AAT-52, or
Transformable, ... the idea being it could be a light machine gun ... on a bipod,
or a heavy machine gun mounted up on a tripod.
So, also intended for vehicular mounting,
they had versions of this with a heavier barrel, with no sights
and no bipod that could be mounted in, say, a tank.
The idea was take that universal machine gun, and do it the French way.
Now these guns were ... originally designed and adopted in 7.5x54mm French,
the standard French rifle cartridge.
Within just a couple of years of adoption however,
... obviously the NATO trials for a new standard NATO rifle cartridge were going on.
And it became clear 7.62 NATO was going to be adopted as a general purpose cartridge.
And so the French started looking into what would be involved in converting the AA-52
into 7.62 NATO, and it didn't look like it would really be that big of a deal.
The cartridges, the ballistics, look very similar,
and Châtellerault figured really not a big deal.
So we'll talk about that conversion in a minute,
but first let's take a look at how this actually works inside.
It's ... sort of a bomb proof, simple kind of gun.
Like I said, there's really not a whole lot going on on the inside of the Model 52.
It's a remarkably simple and effective general purpose machine gun.
So the receiver is primarily stamping, similar to the MG 42.
There is a collapsing stock back here.
Now you can't actually fire the gun with the stock collapsed
because the bolt will hit the stock arms on the inside.
However, it is very easy to extend, and this is just done for
making the gun smaller for transportation, you just pull it back.
And there is no lock when it's in the retracted position, so you just pop this open.
In order to close it you take that lever,
pull it to the side, and you can collapse the stock back in.
It is a belt-fed system, so it feeds in on the left.
... Links come out on the right, and empty cases eject out the bottom.
We have a rear sight up here on the top cover.
This whole top cover is very obviously taken from the German MG 42.
The lever to open it is particularly distinctive.
And like the 42, you also then have a feed tray that can be lifted up.
Now where this differentiates itself completely from the MG 42 is in the bolt operation.
So you'll notice when I pull the bolt back, the bolt body comes back,
the bolt head stays in place ... like so.
That is a non-reciprocating charging handle.
And by the way, the simplifications put into practice here with the manufacture of the gun
mean that you have to have the bolt back in order to close the top cover.
The top cover on the inside is also very MG 42 like.
We have a large lever here that is going to pivot back and forth
as the bolt travels back and forth.
Which causes our feed pawls to cycle here, this pulls the belt ... in that direction.
But when the bolt is closed the system is in this position,
and it is spring loaded such that it will always return to that position.
So you have to have the bolt open in order to close it.
And that's fine, that's part of the loading process.
You have the bolt open and then you can either open it and put a belt in,
or feed a belt through from the side.
The gun was designed using essentially the same bipod as the Châtellerault 24/29.
Of course it was designed by the Châtellerault Arsenal.
It make sense they would use what they had, this had seemed to work pretty well in service.
And we have a quick-change barrel.
In order to remove the barrel, all I have to do is press this lever down,
and then I use the barrel handle to unlock it, and ...
(there we go) and pull it out. Which I'm not quite an expert at doing yet.
A little bit like the M60 here in that your bipods are attached to your barrels.
Less like the M60 in that there is no gas system being attached to the barrels,
because the gun doesn't have a gas system.
I do want to point out that with the barrel removed
this whole package is really quite compact with the stock folded.
This is super short and easy to transport.
So, let us continue with some more disassembly.
Go ahead and pull the pistol grip off next, there is one pin
holding it on here.
Just pop that pin out and the pistol grip comes off.
It's a very simple pull down, drop sear sort of fire control group.
There you go.
And it has a simple fire and safe lever, there isn't a semi-auto option on here.
Next up we can take off the rear stock assembly by unscrewing this pin.
There we go.
That's threaded into this side of its bracket.
Once we have it unscrewed a bit, it will just pull right out.
There we go.
I do have to pull the stock open, and then it's held in place by this lip at the top.
And the recoil spring sets in that little recess.
So our stock assembly just comes off.
By the way, it does have a shoulder rest that you can lift up.
Recoil spring and guide rod.
And then we can pull out ...
this one's a bit sticky inside, there we go.
We can pull out our bolt and carrier.
While we're at it, I will point out that if I lift these up I can take this pin,
and that comes out, which allows me to take off the feed tray and the top cover.
Our bolt assembly is four separate components that come apart.
So we have the bolt carrier back here you could call it, or the bolt extension.
We have the actual bolt head, we have the lever arm, and we have the firing pin.
And I can just pull this right off the front.
The firing pin comes out, so let me start with this guy.
This sits in that little hole there, which fixes its length pretty unequivocally.
And then it runs into that hole in the top of the bolt head ... right there.
And the idea is the firing pin will only protrude out of the breech face
when the bolt is fully locked in battery like this.
And as soon as the bolt starts to open the firing pin ... has to be pulled out
because it's hooked onto the rear piece. So, we've got that.
And we've got our lever arm here, and this is the critical functioning component of this system.
So the idea of lever-delayed blowback
is when the bolt is locked, so to speak (in battery, it's not actually locked),
but when it's fully in battery with a cartridge chambered,
this lug is sticking off into the side of the receiver.
And you can see that recess right here. So that lug is sitting in there.
If we look at the outside of the receiver you can see that this steel block
(which is cut through the stamping there), that is essentially the locking surface.
That's separately hardened, there's this pin
that's holding it in place, down there, so that it can be changed.
And that's inserted into the receiver stamping.
And you'll notice it's asymmetrical, so on the opposite side is just basically a guide surface.
This is the important area.
So when the gun fires, pressure is pushing back on the cartridge.
And this whole thing wants to move backwards, but this is held in place by the receiver.
... We can see if we push on this what's going to happen is it's going to force
the rear portion of the bolt, which is most of the mass, to move backward.
And only when the rear portion of the bolt has moved this far backward
has this arm, this lug, disengaged itself from the receiver.
And so it's now at this point that continuing pressure on the whole assembly
pushes it all back, and that's when it starts to extract the case.
And then of course the opposite happens when it chambers a new round.
... The breech face is going to hit the barrel face, it's going to stop.
The backside of the bolt is going to continue forward being pushed by the recoil spring,
which pushes this lever arm into position inside the receiver.
And what's happening here essentially is this arm is
(because it is ... of unequal lengths, this side is longer than this side),
it is magnifying the effective mass of the rear half of the bolt.
Forcing it to move backwards before the bolt head can move.
And that basically gives time for pressure in the barrel to drop so that it can open safely.
This was a system developed by a Hungarian designer by the name of Pál Király,
who used it in a couple of guns. It was used in a SIG submachine gun in the 1920s.
It was used in a .30 calibre carbine
designed actually with Király's help in the Dominican Republic in the 1950s.
And then the system was used in the AA-52 and later the FAMAS.
And that's pretty much all of the lever-delay blowback
firearms that ever saw significant production.
You can see the cuts on the top here that are going to operate
in tandem with this lug right here in the top cover to cycle rounds in. ...
One other important feature on here is this surface right here, that's the sear surface.
That is what engages with the fire control group.
And when you pull the trigger that drops, which allows this to move forward.
It does reset off of that coming backward
to catch the bolt and stop it once you've released the trigger.
And there it is all field stripped, the AA-52.
Really a remarkably simple, kind of bomb proof sort of light machine gun.
Compact to get around, all the features you'd want.
And none of the creature comforts that you shouldn't be accustomed to if you're in the army anyway.
By 1964 the Châtellerault Arsenal had finished its testing
and development on converting the AA-52 into 7.62 NATO.
It proved to be a little more difficult than everyone thought it would be.
There were a number of modifications that were required.
We'll go into all those details in another video when we take a detailed look
specifically at the AA F1, which is what that conversion became designated as.
Fundamentally the gun remained the same,
just changes to a bunch of details and small parts, new bipod.
Anyway, this is an interesting development in that ... it is during this time
that the French were looking at generally standardising on 7.62 NATO.
And, as we have a separate video on, came to the conclusion
that they just weren't going to for a rifle. But they did for their universal machine gun.
Which was this, the 52 turned AA F1.
Anyway, in AA F1 guise, these are still in some military service with the French Army.
So really a pretty long lasting gun, and a very interesting one.
One of very few examples of lever-delayed blowback.
Obviously after this came out the FAMAS would go ahead and
use that same principle itself to great effect. So.
Anyway, a big thanks to the IRCGN collection for giving me access to come in here
and take a look at some of their particularly interesting guns to show to you guys.
Hopefully you enjoyed the video. Thanks for watching.
[ For some shooting footage and another perspective on the AA-52, check out Bloke on the Range's video today! ]