[ Savage M1918 Aircraft Lewis Gun ]
Hi guys, thanks for tuning in to another video on ForgottenWeapons.com.
I'm Ian McCollum and I'm here today at Morphy's
where we are taking a look at a US
World War One aircraft machine gun.
Specifically this is a Lewis gun Model of 1918,
manufactured by the Savage Arms Company
of New York in .30-06 calibre.
So this is basically the final iteration
of the Lewis in Air Service configuration
for the United States military.
Now there are a number of obvious changes from the standard Lewis ground gun.
The two that really jump out are the fact that it has a single spade grip at the rear,
and that whole, very iconic, cooling shroud
that was what made the Lewis kind of a thing, is gone.
Well of course, if you're flying around at altitude at 100 miles an hour or so,
you don't really so much need specialised cooling equipment.
Just leaving the barrel out in the slipstream is perfectly effective.
On top of that, there wasn't a lot of sustained fire in air-to-air combat.
You might fire as much as you could in a short burst
when you had someone in your sights.
But it wasn't like you were dumping magazine after magazine,
you just didn't have the opportunity.
So the barrels didn't get that hot in the first place.
And if you can shed the weight - shed the weight.
These early airplanes needed ... every ounce you took off the aircraft
was that much more speed, climbing, manoeuverability, etc.
So, we've got rid of that.
Now of course we have kind of added some weight back
by giving these extra-large magazines.
Where the standard Lewis had a 47 round pan magazine,
the aircraft guns had double that.
Well, approximately double that, 97 rounds in a taller magazine.
Obviously you want to be reloading as little as possible
when your other job is shooting at people and flying the airplane.
Now, there were a number of different guns that
saw World War One aircraft use for the United States.
In particular we had a lot of Vickers guns that were put into aircraft.
And the big difference in practical use
between an aircraft Vickers and an aircraft Lewis is that a Vickers fires from a closed bolt.
Which means the ... cartridge is chambered, the bolt is closed and locked.
And when you pull the trigger all it has to do is drop a striker,
hit the primer and fire the cartridge.
The Lewis is an open bolt gun, meaning that when you pull the trigger
the bolt actually closes, feeds a cartridge into the chamber, locks, and then fires.
So there is a much greater, and much less exactly predictable, delay
between pulling the trigger and the gun going bang in an open-bolt gun like the Lewis.
The practical implication of this is it's very difficult to synchronise a Lewis gun.
The whole point of synchronisation is the best place to mount machine guns
on a World War One airplane is pointing right in front of the pilot,
right through the arc of the propeller, so that
you just aim the aircraft at your enemy aircraft and fire.
And it greatly simplifies things. ...
There's a downside if you shoot your own propeller off though.
So during World War One a series of mechanisms were developed
so that you could safely fire between the blades of your own spinning propeller.
And that required a consistency of timing
that you could only really do effectively with a closed-bolt gun.
So, going the long way around this, the Vickers guns, closed bolt,
got used as synchronised guns primarily on fighter aircraft.
The Lewis gun, being an open-bolt gun, isn't really suitable to synchronisation,
so instead they get used ... in alternative positions.
So there are some aircraft where ... on a biplane they would mount
a Lewis gun on the top wing of the aircraft.
So it's lined up laterally with the pilot,
but it's lifted up above the arc of the propeller, that's one option.
There were also a number of aircraft that had multi-man crews
where you would have an observer, who could have a gun mounted in a flexible ring
(typically a Scarff ring, that was the most common pattern of them),
which you could then swing around and point anywhere,
and have a much greater field of fire.
An open-bolt gun was just fine for that.
And the Lewis was a particularly suitable gun for observer flexible mounts,
the fact that it used a drum magazine instead of having a belt.
... On a fixed gun the belt's not a big deal, ...
you put a spindle somewhere in the fuselage and it'll feed straight through the gun, easy.
If you're going to be swinging the gun all over the place,
you have to accommodate for a belt coming out one end when it's empty,
and a big spool of 100, 200, 250 rounds of ammunition somehow attached to the gun.
The magazine feed greatly simplifies that.
... There are a couple of other changes they made to the aircraft mags,
which we'll take a look at in a moment.
So that is why you have a spade grip back here.
You didn't need a full stock because this thing was mounted ...
typically in an observer's ring mount.
You don't need the cooling shroud, you do need the extra ammunition,
and you do need special sights.
So this is a Norman wind vane sight,
which gravity has dropped down like this at the moment.
The idea of this is if you are in this observer's ... front or rear seat,
depending on how that plane was configured,
if you're in this observer's position
you ... have like 12 things you have to calculate to try and make hits.
Think of shooting at a moving target.
Now think of also shooting at a moving target from a moving vehicle,
and both of the vehicles are moving in three dimensions, not two.
You have to somehow account for the angle of your own aircraft, the wind,
so if you're firing straight ahead, that's one thing,
there's going to be no impact of the wind pushing bullets to one side or the other.
But if the plane's going this way, and you're shooting this way,
you're going to have ... to give significant lead to account for your own movement,
plus lead to account for the movement of your target.
The idea of this wind vane sight is that it automatically
compensates for movement of your own aircraft.
We'll take a look at this up close in just a moment.
So as I said, these are in .30-06, this was the American pattern of the Lewis gun
with a number of mechanical changes, which I think we'll
probably not get into in detail for this video.
But, this is the 1918 pattern, so let's check it out up close.
There was some conversion of ground guns to aircraft use,
but Savage manufactured these from the ground up as aircraft guns.
So you can see under the magazine here,
Lewis Aircraft Gun, Calibre .30, Model of 1918, and a serial number.
That serial number ... includes a lot of different Savage guns, and not just aircraft guns.
A little farther back under the top cover effectively, Lewis Machine Gun with the Savage logo.
Note that it is marked ".30 US Government", that's .30-06 calibre.
That is to help distinguish these from .303 calibre Lewis guns
that were in mostly British service,
but there were also some of the .303 guns in US service.
Probably the easiest way to differentiate .303 and .30-06 Lewis guns,
both ground and aircraft, is to look at the side above the trigger here.
So this is the safety bar, it's currently locking the charging handle in position.
And it can lock it open or closed, and I can pop that down.
On the .303 guns you have this on both sides.
On the .30-06 guns you do not, the right hand side is solid.
And this is where the markings are roll stamped.
So this, the slot or lack of slot here,
is something you can typically see pretty well in a lot of photographs.
And it's also something you can easily spot from the outside of the gun
if you're looking at it in person.
So on the receiver here we have patent dates.
This gun's been refinished, so the markings are a little faded.
We have US Cal .30 right there, again faded, a little difficult to see, but it's there.
And Lewis Machine Gun, manufactured by Savage, Utica, New York.
I believe what we had here was originally a Navy registration number that has been removed.
The Navy gave their Lewis guns their own numbers,
in addition to the serial numbers that were put on them by Savage.
Now I want to talk about magazines for a minute.
This is the standard 47 round Lewis pan magazine.
The design is identical between the .303 and the .30-06 versions of this,
but they are not interchangeable of course because of different cartridge dimensions.
It is very difficult to tell them apart, so the .30-06 ones are conveniently marked "30 US".
Now in order to remove this from the gun you have a switch right here.
And you just push that in and lift the magazine out.
Now I want you to consider for a moment the situation
of an observer/gunner using one of these Lewis guns.
It's really cold, you're up at altitude, you're going, I don't know, 100 miles an hour.
And your hands have to be outside in the slipstream
because that's where the guns are mounted.
You're going to be wearing thick gloves, and that
is going to be an extremely difficult operation to do.
So they didn't even try to have aircraft gunners do that.
Instead we got magazines like this one.
So you can see that internally it is the same exact design.
They've added these struts just to help support the outside of the magazine.
But basically where the standard Lewis magazines have
two stacks of cartridges, the aircraft ones have four.
It is also marked "30 US".
And the release latch is now a thumb lever over here,
and you've got this leather strap.
And the idea is to mount the magazine you put your gloved hand
(which is why that's a pretty large strap), you put your gloved hand in here.
That allows you to control the magazine, put it onto the spindle of the gun.
And then to take it off you put your hand in,
and you can use your thumb to depress that lever, and pull the magazine up and off.
So ... the British of course had .303 calibre ... aircraft guns and 97 round drums like this.
They used the same sort of pattern as such.
If you're looking at the inside of the gun,
there are a few distinctive elements besides the markings to a .30-06 gun.
One of them is the length of this cut.
On the .30-06 this comes almost right up to the centre magazine spindle,
on the .303 guns it's substantially shorter.
And we also have a few little things like the rear sight being marked ".30 US".
Interestingly the British would later develop
an extended trigger guard to better fit gloved hands.
The US didn't during the course of the war.
The examples of ground guns converted to aircraft use
will typically have a few inches of that aluminium radiator shroud
still on the gun, cut at a bevel front and back.
The purpose-built aircraft guns don't, they just don't need it.
Instead they have a socket here that's built in to hold the barrel,
to hold the gas system, the gas operating rod down here,
and also to act as a mount for the ring mounts in the aircraft.
Or, theoretically, even a ground-mount tripod.
It was important to protect the gas piston.
Normally in a ground gun that's something that's done within the aluminium radiator shroud.
The aircraft gun, without having that component, needs its own standalone gas system tube.
So the 1917s had a less substantial protector.
Some of the early ones actually used a wooden handguard down here.
1918 they added a metal purpose-built protective tube there.
We also have a fairly distinctive muzzle brake that was added to the guns.
And that was done deliberately to increase their rate of fire.
A typical Lewis gun is going to be something around 500 rounds per minute, relatively slow.
They wanted a higher rate of fire for aircraft guns
where you have fleeting opportunities at targets.
And so this was one of the things to do that.
The idea is, while it produces a lot of blast and concussion,
it does actually put more back pressure on the system,
which is going to speed up movement of the bolt, that's the idea.
So these were added as a factory element on the 1918s,
and they were retrofitted onto 1917 pattern guns.
The specific markings on here, we have International Register Company, Chicago,
who were the main manufacturer.
And then these notches are velocity increments.
You would not obviously reset these while you're in flight,
you would pick, "What is the most likely engagement speed of this aircraft?"
And these are in increments of 20 miles an hour, they're a little hard to make out, but
starts at 50, 70, 90, 110, 130, and 150 miles an hour. This one's currently set to 130.
And of course, the higher the velocity of the aircraft,
the greater the deflection in any given orientation.
So that's why you would want to move the post,
farther away to go faster, closer if you're going slower. ...
That's your actual front sight post,
and this wind vane basically acts as a drag resistance.
So if you're flying around and you're going that direction,
wind resistance is going to swing the sight like this.
That is going to move your front post substantially out away from the barrel,
which gives you proper deflection for accommodating the aircraft movement.
And it does this in the vertical plane as well as the horizontal plane.
So it won't ... account for your target moving,
but it at least takes your own aircraft basically out of the equation.
These appear to have been fairly accurate, it's hard to say for sure,
but they were used by all of the Allied forces who had aircraft guns like this.
And they continued to see use after the war,
which tells me they weren't just a wartime experiment that didn't work.
The rear sight to go along with that was this, basically just a centre post.
You put the knob at the top of the front sight inside that aperture,
and that's your straight-on sight.
The ring is here as an estimator for target speed.
So this would ... give you the proper lead.
So instead of putting your front sight in here, you would put your front sight on the ring
depending on the range to the enemy aircraft, and the estimated speed of the enemy aircraft.
So when you see spider-style sights that have several rings,
those multiple rings indicate different target speeds.
... Being an aerial observer/gunner was a really tricky job,
and there was a ton of math that you had to do in your head
(or by gut in probably many cases),
to actually get hits on moving aircraft from moving aircraft.
In total, by the Armistice at the end of World War One,
Savage had produced 32,231 aircraft pattern Lewis guns.
Now that includes 1917s and 1918s, but a lot of the 17s were updated
with things like the recoil booster to more of this pattern.
... As I said at the beginning, they were used primarily as observer's guns.
De Havilland aircraft were a primary user of these for the Americans
during World War One, DH.4s and DH.9s both.
Today they are pretty darn cool.
There is actually a very rare mount that was developed
to be able to set an aircraft gun on a ground tripod
to actually shoot it from the ground.
Because there's no real effective way to hold onto this thing for shooting from the ground.
So we actually have one of those here at Morphy's right now.
And we're going to take this thing out, and mount it up on a tripod,
and do some shooting with it tomorrow.
So stick around for that video. Hopefully you enjoyed this one.
Thanks for watching.