Welcome back to Arsenalen. We are doing a tour of the Sherman VC,
commonly known as the Firefly.
Now I'm going to set a level of expectation first.
This is the best firefly
that I could find to do a tour of,
but it is not complete.
However we should still be able to get
an idea of how much room in the turret was set aside
for the gun and how much room
was set aside for the crew.
So there not being very much on the outside of the turret
except for the mounting point
for the commander's machine-gun.
I've come on down,
closed the turret doors,
and you can see what the commander has to look out of.
And it's basically,
there would be one periscope here:
Rotatable, adjustable in elevation,
and because the cupola would swing around,
you could bring into the front.
This is quite miserable,
but it was the standard Sherman hatch in the early design.
Fortunately the British
and also the americans eventually,
they developed vision cupolas
and the vision cupola had periscopes all the way around,
it was a substantial improvement.
A number of fireflies were equipped with it,
obviously not this one.
Controls, he has a commander's override.
Again, this vehicle was
disassembled for testing purposes.
We're dealing with what's left.
Commander's override, of course,
allowed him to lay the gun onto target
much faster without having to direct the gunner,
that yelling at him over the intercom
to figure out where he's going.
To the rear you can see that they have cut out,
and this is actually a pretty good job,
the rear wall of the turret.
Now Fletcher's book says the one at Bovington
is roughly cut, maybe they had
an early one or something,
but back here would be the number 19 wireless set,
and it was moved out of the way
not because somebody worried about the recoil of the gun
hitting the radio, highly unlikely,
but just to be a lot safer to the access of the controls
just in case the gun did go off,
and of course there was also the additional
counterweight issue that I mentioned.
In terms of space well you can see I'm already
pretty cramped down but I'm tall,
that's not too unusual.
The gunner's seat is a little close to the TC's,
and a lot of my real estate and taken up
by the very large breech recoil guard to my left,
so you should be able to see hopefully a little bit of that.
So before we go on to the next to seats,
the gunner and the loader,
since it is going to be the focus of their jobs,
now is as good a time
as any to talk about the 17 pounder.
It was well known
for being serviceably accurate and quite powerful.
The catch is that it wasn't really designed
to fit into a tank,
let alone fit in a tank designed
to have a medium velocity 75.
It is commonly viewed that in order to get it to fit,
they had to rotate it 90 degrees
and then stick it into the turret,
and this is a gross oversimplification.
The first problem was that in the towed mount
the run-out was about 40 inches
and there is not 40 inches
of recoil space inside this turret.
They had to change this down to a mere 10 or so.
To do this they took the recoil mechanism
from the six pounder, basically,
and they upscaled
that design so you have recoil cylinders
on opposite sides of the gun,
one up and right, the other low and left.
The next thing they had to do is they had to shorten
the cradle in order to get the thing to fit into the turret.
This meant that you had less support on the gun.
That then meant that they had to reshape the gun tube
in an order to have a similar amount of contact support
as the ground mount had.
Then, they had to change
the breech to operate horizontally,
but it was the complete redesign
because you still have the operators
who want to open and close the thing
and otherwise do maintenance,
well they have not been rotated 90degrees.
Once you have all these changes made
you now have the Ordnance, Quick-firing,
17-pounder mark 4, the basic tank cannon,
the one in here is the mark 7.
The main difference
on this was a delay in breech opening.
The mark 4, for it when you fired the round,
especially a high powered round,
you had a lot of flashback from unburned propellant.
They have a video running in the background
here at the Museum,
there is an old Firefly crewman saying
that they could always tell the firefly crews
on parade because they were the ones
with no eyebrows and no hair below the beret line.
So that about tells you the back story
and let's move forward quickly
to the Gunners position.
So in the gunner's seat,
I'm going to have to ask your indulgence
a little bit of creative disbelief.
This traverse system is supposed to be up here
but it weighs more than I can lift at these angles
at my height so just use a little bit of thought there,
may be something for the CG artists, we'll see.
The British very much liked
the Oilgear power Traverse system
so any Sherman which was converted to a C model,
if they didn't have an Oilgear system,
they had one installed.
They provided very fine ability to adjust on lay,
they did like it like a lot.
However, I wish I could say kind of the same
about the rest of the configuration.
There is a manual traverse
which would would have gone here,
there is a power Traverse
right in the center.
You will see that unlike the standard American one
where that is the middle,
and then you go right, go left,
this is angled off a little bit
so that the center position is off to the left.
So that is full right, and that is full left.
The reason they did that is the ungodly position
of the elevation handle
and this is only manual elevation.
The gun itself was reasonably well balanced,
it was balanced for an empty chamber,
but allow me to demonstrate
how you reach down to the elevation handle.
I am now holding said handle,
and my head will go here at the sight.
I'm at absolute full extension,
and there is a horizontal bar which limits liability go up,
the recoil guard limits my ability go back,
and i actually would find a kind of difficult
to get any sort of leverage
if i'm looking through the the periscope
at the top right.
Now, how easy it was to perform in duress…
I mean I guess adrenaline
gives you a little bit of help.
Certainly in the American trials
they did not like the position
and I can understand why.
The stabilization system
has been completely removed,
which I guess at least frees up a little bit of space,
but it also means that you've lost
the ability to fire on the move
if you wish to do so.
To see out, his primary sight would be here,
a Number 43.
It is a by-three optics,
13 degrees field of vision
and graduated with two range scales.
The one on the left was the main gun,
APC and HE on the same scale,
graduated to 4,000 yards
which is a odd considering
different muzzle velocities,
one was about 3150 and the other one
that 2,900 feet per second.
On the right hand side
would be a machine-gun scale.
Your alternate sight was the original one
that came with the tank:
A 75-millimeter sight inside the m4 periscope
with M38 telescope.
Because this was the original sight
they had to install a conversion chart
on the turret wall
that basically said
"ok if you are aiming with apc on the 17 pounder,
this is where you have to aim on the periscope",
so for example two thousand yard actual target,
use the three thousand yard aiming point.
Fortunately most of the fighting
was done at really short range
and the 500-yard mark was
right in the middle of the aiming circle,
so you didn't have to think about it very much,
just slew on to target, aim center mass,
you'll be good.
August of 1944 a new round is deployed to the troops:
Super velocity discarding Sabot.
Now, the catch was that it did not deploy
new reticles for the guns,
so you were supposed to take whatever the range was,
divided by 2,
and that would be super elevation
on the APC scale that you would apply.
Now one of the big problems
with the SVDS rounds
was that at ranges
where there is any notable deviation
between the trajectory of APC
divided by two
and the svds round,
you're looking
at an exercise of the purest optimism to begin with.
The British figured maybe 500 yards
was the outer limit of range,
the Americans just found it to be completely
unacceptable in post-war testing.
Worse, if you fired a couple of rounds of SVDS,
you end up with some duraluminum fouling,
and that would destroy
the accuracy of the follow-on rounds.
Not that the firefly really
needed the SVDS though.
Ok, everybody talks about it
and how it's got a wonderful
nine inches of penetration
against a 30-degree steel target
at the muzzle
but in practice there wasn't
exactly a heck of a lot that the regular APC round
couldn't beat about a bit
if it encountered one on the battlefield.
For the process of target engagement,
an infantry rangefinder was issued
on the basis of one for every troop.
The command would be something like,
Gunnar Traverse left, steady, on,
one eight hundred, Hornet.
The British manual seems to imply
that there are code names for all sorts of targets:
"ant" is a transport etc,
so I would assume a hornet
is something which stings,
like maybe a tank.
I strongly suspect, however,
that in the field these code names
went out the window
and they simply reverted to using plain English
and keeping it simpler.
Once you have the range,
you then engage,
and this brings us to the next problem,
and I'm going to quote something
from the manual that I've transcribed here.
"The fundamental difficulty
with 17 pounder shooting lies in observation.
Muzzle flash, blast, dust, fumes,
and the repercussion of the vehicle
as the gun fires makes observation difficult.
It is almost impossible to
observe the tracer at ranges of less than 800 yards.
The crew, especially the gunner and commander,
must be trained to close their eyes
at the instant of firing"
It also mentions
that the TC need to brace himself to hold
his binoculars on target
and suggests the use of a flank
observer to see whether or not
you're hitting anything.
Another option it suggests is to fire
a couple ranging around with HE
on the basis that the burst at the other end
is going to be very easy to see
and you can tell whether or not you're on target.
To actually fire, he's got foot triggers,
one on the left one on the right
for the coaxial and the main gun.
Initially it was reversed
but they figure that was confusing
since the gun is on the right
and the coax is on the left.
I think I've rabbited on enough
about the gunner's position,
now I'll hop on over to the loader now.
So, the loader's side.
Now just to put this thing into perspective.
1942, US Army ordnance
approved for production the m4 76mm.
That was an attempt to stick the 76 millimeter
into this small 75-millimeter turret.
Ordnance were happy.
After it was ordered,
Armored Force grabbed hold of a couple,
and they said
"look, it's fine for you to declare it works
but you don't have to use the damn thing,
and as a result they canned the whole project,
sent Ordnance back to the drawing board,
it took them an extra year to get the 76
millimeter really sorted.
The reason I bring this up
is that the 76 millimeter is somewhere around
half the weight of the 17 pounder
and is a somewhat smaller gun,
and if Armored Force
thought that was too big to be practicable,
one must wonder
about the perspective of the British.
Now the first problem
that they had with the larger breech
was even getting into the loader's place in the first place.
You will recall for the m4
I was not exactly complementary
about the fact that some designer
decided not to put a loader's hatch in the turret,
and it would appear that the british
felt more or less the same way.
They came to the same conclusion,
especially motivated
by the fact that they have
an even bigger breech to work around,
and that conclusion was
"let's give the loader a hatch."
Good idea.
So they cut out this square hatch here,
they give it a spring-loaded assist to help
the loader open it up,
and life became much better.
Another option would be that
if you remove the rest of the recoil guard
such as been done here,
the commander's side will hinge up
and out of the way,
and you get around the back that way.
For the sake of an experiment,
I'm going to beg your indulgence.
I'd like you to imagine, please,
that there's a little bit more inside this tank
than you can see.
So, for example you have the bomb thrower
here looks like a big pistol,
you've seen in other videos
with maybe a little bit extra
ammunition on the side.
Your periscope, ok.
The Browning 1919 coaxial machinegun
with the spare ammunition
stowed here on the left
and of course his ready rack of five rounds
which are stowed on the side,
that's all the ammunition
that is relatively available to him,
plus the one in the tube.
The last piece of imagination
I'd like you to use is that
this is a 17 pounder round.
This is actually smaller
than a 17-pounder round,
its a couple of centimeters shorter
and it's definitely narrower,
but it's best we can find. If you're curious,
we grabbed it out of the Stridsvagn 74.
So you would somehow manhandle
the round out of the ready rack,
bring it back into the bustle of the turret
that will clear the nose of the round to go in
towards the breech,
and hopefully the gun isn't at too high an elevation
and you can actually do this.
You then would have the recoil guard
around here so you're going to be careful
avoiding that
and then bringing around
forward twisting it sideways a little bit to straighten it up
and then into the tube you can go.
Rate of fire was not particularly
high for a couple reasons.
Firstly, the manhandling.
The second problem was the obscuration problem
so you couldn't really fire again
until you were able to see again,
and the third problem was
that with only five reloads available,
you were going to run out
of the appropriate very quickly.
So let's say you have three AP
and two HE rounds,
you fire off your two HE rounds
and then you're stuck looking around
your long-term stowage.
77 rounds were available in the vehicle.
In addition to the five in the ready rack,
there is another 18 forward
under the turret, kind of behind the driver.
Forty more would be carried
on the right hand side under the turret,
and they're relatively inaccessible,
and the final 14 were in the former
bow gunner's position.
Although it was possible
to pull most of the those straight from the bow
gunner's position back into
the loader's position
with the turret spun around
it was usually easier to simply climb out
and lift them up through the hatch
and then down into the turret roof.
This is the price you pay for putting a very powerful gun
into a really small turret.
If that was a good idea
while we can debate that a little later.
Do that's done let's go
forward to the drivers position.
I've always been very comfortable
in American tank drivers' positions
and the M4A4 is no exception.
I'm sitting on a very comfortable seat which,
of course, will elevate sufficiently
to allow me to drive open hatch.
Foot on the clutch, lots of room,
on the accelerator, grab the steering tillers,
no issues in the world.
To the right, the gear lever is easily accessible,
i'm not going to bash my arm into anything
as I use it, can't complain at all.
The transmission is big,
it is not in the way.
The panel, you would expect with an engine
as complex as A57, actually isn't.
In fact, about the only indicator
that there is something a little bit strange is
that you have a slew of exhaust stack
temperature warnings.
Five of them, for the five exhausts
that are coming out.
Everything else is pretty much
what you would expect standard,
one oil pressure gauge one temperature gauge,
so on and so forth.
This tank was used for a while
after the nineteen fifties for the s tank trials
and it was being used to test
whether they could steer correctly.
Looking at the drivers' position you don't see anything.
In fact on the whole tank,
the only real giveaway is the weld marks
for the i-beam
that they had used to represent the gun.
Those weld mark are still
on the front slope of the tank but that's it.
It's pretty much the original drivers configuration
as you would expect it.
They even left the builder's plate here
so according to this it's M4A4 number 176 733,
if any grognards want to look at one up.
If you look aft you do see that they cut away
part of the turret basket to make
room for the 17 pounder's elevation gear,
and of course being a small hatch, well,
the good news is it's directly above you
and spring-loaded, so pop and out you go,
quite quickly and in a hurry if you have to.
The bad news is it's a bit narrow
and it's kind of tough to get out of especially
if you're worried about hurting yourself
or ripping something.
However, I shall do it now. Use the small hatch
and then we can go on to debate
the merits of the conversion.
So that's it, our second Sherman.
About 2,000 Fireflies were built,
they were distributed
among the various Commonwealth countries.
Now onto the effectiveness.
It is said that the Germans were told to shoot at these things first.
The British went to great lengths to try to conceal
the extra length of the gun.
Now I haven't seen any documentary evidence to say
that the Germans actually had such an instruction
and I have my doubts as to whether
or not any German would have actually done so
and ignored a tank that was an immediate threat.
Still the firefly loss rates were less
than those of other tanks,
and it could be because of the camouflage
or could simply because the British hoarded them
a little bit to the rear to be used as a sort of reserve
against any tanks which showed up.
Indeed in Italy, the fireflies
were taken as separate troop,
and their job as a troop,
or platoon in American terms,
would be to cover the rest of the company.
Now your opinion on Firefly is probably going
to depend on a couple of different factors,
and well frankly.
no opinion is necessarily going to be wrong on
this one because it's all a matter of perspective.
Your first question is do you want a tank
or you want a tank killer.
This was a tank killer.
As a general-purpose tank it suffered a couple of problems.
Your second question is, well,
do you want something that's ok now
or you want to wait to get something
which is excellent later.
Again this brings you to the difference
between the 17 pounder sherman
and the 76 Sherman.
17pounder on the D-Day was present.
The 76 was not. Although i would argue
that the 76 was overall a better vehicle than firefly,
it was during those critical periods of time in Normandy
that the Firefly established its reputation.
So anyway, we're going to go back to look
at a few more Swedish tanks
in the next episodes,
so we'll see you there.
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