Hi guys, thanks for tuning in to another video on ForgottenWeapons.com.
I'm Ian McCollum hiding back here behind this huge machine gun.
And what we're actually looking at today is a water-cooled .50 calibre Vickers gun.
Specifically this is a Mark IV, we'll go over what the differences were.
But this is a project that Vickers began just after World War One,
well, the development began during World War One.
Everyone was starting to look for heavier and heavier machine guns,
primarily for both aircraft (and anti-aircraft), and armoured vehicle use.
The .50 calibre cartridge ... that was really developed and put into service
during World War One was the German 13.2mm,
originally developed for their Tank Gewehr anti-tank rifles.
... The Germans were working on a [13.2mm] calibre Maxim gun that would have used it,
... called the "Tank und Flieger", the Tank and Aircraft gun.
And everyone else kind of started doing the same thing,
but no one else got them into production during World War One.
In the US this would ultimately result in the Browning M2,
and the venerable .50 calibre Browning Machine Gun cartridge.
In Britain this led to the .50 calibre Vickers gun.
Now, ... the first batch of these were purchased by the British military in 1921.
And it was like 16 guns.
And that program actually kind of dead ended there,
and it didn't lead directly, or not for a while, to guns like this one.
This is kind of the reinvigoration of the project in the 1930s.
So to start with, the cartridge that this uses is not the .50 BMG cartridge that is so common today.
This is the .50 Vickers cartridge, actually one of several .50 calibre Vickers cartridges.
This was a 12.7x80mm cartridge, so substantially shorter than the American .50 calibre.
It fired a 580 grain bullet at about 2,540 feet per second.
So it's a shorter cartridge, it's a lighter bullet, and it's a lower velocity than the US .50 calibre.
Which is part of why it's able to be a much smaller gun than the ... .50 calibre Browning.
Now later Vickers would introduce a high velocity version that was a 12.7x120mm case,
which was huge, but those saw almost no sales and use.
So in the 1930s ... the same two uses really still exist,
this is now for anti-aircraft and for armoured vehicle work.
The idea of putting these guns in aircraft was abandoned,
largely because at the time - before you really got into metal skinned and larger aircraft -
the World War One and inter-war style of aircraft weren't really more vulnerable
to a .50 calibre projectile like this than they were to a regular rifle calibre .303 calibre bullet.
And in experimentation the British found that the .303 Vickers would do
basically just the same amount of damage while having much lighter ammunition,
so you could carry a lot more ammo.
And you could also have a faster firing gun than a .50 calibre Vickers.
So these get relegated instead to anti-aircraft use in a naval application,
and guns like this one that were meant for use in armoured vehicles.
Vickers built a number of styles of light tank during the inter-war years, in the 1930s,
and in particular like they had one that ... had a little turret with two machine guns.
It had a .303 Vickers, and it had a .50 calibre Vickers,
and that's the sort of application that these were really used for.
So relatively compact, they can fit inside the turret of the vehicle.
And mechanically, this is really just a big huge Vickers gun on steroids,
it works exactly the same way that the standard rifle calibre guns do.
So let's take a look at the outside, and I'll show you a few of the things that are different.
Obviously this is set up with a pistol grip,
and it has a few different elements, including a semi-auto switch.
So mechanically this is a massively oversized Vickers gun.
And you can see we have all the same sort of elements: we have
the charging handle here, which is going to cam back against this roller right there.
So when this fires the barrel recoils backward, the action bars here recoil backward.
This roller is going to cam the charging handle open like so,
and it's going to cycle just like any other Vickers gun.
Now this has been set up with a pistol grip
because this was to be mounted inside an armoured vehicle,
and fired with the shooter's shoulder back up against this.
So there is a dovetail on the back of the receiver block right there.
Unfortunately I don't have a shoulder stock to drop onto it to show you,
but that would have been basically just a heavily padded shoulder rest right there.
There is a pistol grip with a two finger trigger here.
And there is actually an interesting grip safety on the other side.
In order to fire, the grip safety has to be pulled down,
and it actually has to be held down the entire time.
If you release it, the trigger won't move.
So you have to hold this down with your thumb while firing with these two fingers.
In addition, unlike a regular Vickers gun, the calibre .50 version
is set up with a selector switch for "R", repetition or semi-auto, and "A" for automatic.
Now the way that works is built into the top cover.
So where a standard Vickers opens front to back, this pivots open on the side.
And we have this little arm right here.
In automatic mode when the trigger is pulled, that bar comes backward like so.
And it will stay backward as long as ... the trigger is held down.
And what this does is ... cycle the trigger up here.
Which trips the ... sear in the lock, right there.
Now if this is set to semi-auto, when the trigger is pulled this bar comes back,
but it's not held back, and the spring on the top cover will
push this back into position, and it actually acts as a semi-auto reset.
These guns were all serialised with "G" prefix serial numbers for the ground guns,
the aircraft use ones had "A" prefix serial numbers.
This is number 207, this is a Mark IV gun as a result.
Mark I was the very first.
The original Mark I guns did not have the semi-auto feature, so Mark I was the very first version.
Mark II adds the semi-auto trigger setup. Mark III was the naval specific version.
Mark IV modified this dovetail mounting bracket
to be interchangeable with the .303 calibre tank guns.
And by the way, this is the ejector tube here.
On a normal Vickers gun cases just eject out the front of the receiver box.
On the armoured vehicle guns they wanted to make sure that
the ejection would ... actually spit out in front of the mounting.
So outside of the armour of the vehicle that it was being mounted on,
hence the length of the ejector tube.
Anyway, the Mark IV guns had a mounting bracket ... interchangeable with the .303 guns.
And then the Mark V had a number of parts strengthened for better long-term durability.
Mark V guns would constitute the majority of the production,
everything from like ... serial number 283 up was a Mark V.
We do also have access here to the feed block, the rather huge feed block.
So instead of a lever lock as on a regular Vickers, this has a trigger-like spring.
Allows us to open that up, and then we can just lift the feed block right out of the gun.
For comparison's sake, here's the .50 calibre feed block alongside a standard .303 feed block.
So, you can see the size difference there, this .50 calibre is really quite a massive contraption.
And we can do the same thing with the [locks], again .303 and .50.
So really the design is exactly the same.
This works identically to the regular Vickers gun of general familiarity, it's just bigger.
Over on this side we have the other elements you would expect from a Vickers gun.
We have a fusee spring. Mostly exposed, it doesn't have a cover on it,
because again this was intended to be used inside a vehicle.
The ejection ... side of the feed block for the empty spent casings. And so on.
A few basic facts about these statistically: the gun itself weighs 56 pounds,
plus it took an additional 10 pounds of water to fill the cooling jacket.
Rate of fire for the different models varied between about 500 and 700 rounds per minute.
And the standard belt for them was a 100 round belt.
Obviously the ammunition is substantially larger than regular .303,
and that affected the size of the belts that could be effectively stored and used in the guns.
For comparison's sake here is the Vickers 12.7x80mm cartridge, that's what this particular gun uses,
here's a .303 British cartridge for comparison.
And just for further comparison, here's your standard Vickers feed block,
which this clearly is not going to fit into.
There were never all that many of these guns manufactured,
especially not by World War Two standards.
So, they were tentatively adopted in 1933 for armoured vehicle use.
A grand total of 1,117 of them were made for that purpose.
That doesn't include the naval guns, which are kind of treated separately.
And they're a separate model of the gun, the naval guns were the Mark IIIs.
They were formally declared obsolete in 1944, although they were clearly obsolete before then.
These saw a little bit of use in places like North Africa.
The Long Range Desert Group did have some of these along with their Vickers K guns.
They would be used in various small British tankette sort of vehicles, which
were around for a while, even though they weren't necessarily front-line vehicles.
Ultimately these guns would be replaced mostly by American Browning M2s
that were ubiquitous and far cheaper to get than Vickers.
This is old world manufacturing on a very large scale, and these were
tremendously expensive guns to manufacture and for the British government to purchase.
And they were also in part replaced by guns like the 15mm BESA guns.
So water cooling had become obsolete, the guns were too expensive,
and there were a lot of other more modern options available on the market.
So they remain obviously, not surprisingly, very rare today.
So it was very cool to get a chance to see this one, which I believe
is the only registered example in the United States.
So a big thanks to the collector who owns it for the opportunity.
Hopefully you guys enjoyed the video.
Thanks for watching.