British Sherman firefly

[Slapdragon]

<blockquote>quote:</font><hr>Originally posted by Graaf Spee:

Are you sure that it's iron? I have always heard that it was lead.

Maybe I'm confusing it with the shotgun calibers where 'they' use one pund of lead divided by the caliber. When I think about it it actually makes sense, shotguns use mostly lead pellets(?)but with guns you would want something harder.

/Kristian<hr></blockquote>

Yes, iron, as lead was never used in cannon (to heavy actually).

[Brian]

<blockquote>quote:</font><hr>Originally posted by Slapdragon:

Yes, iron, as lead was never used in cannon (to heavy actually).<hr></blockquote>

Too expensive, more like.

[Ex Bellator]

Great post about the 17pdr & 77mm Brian

[Commissar]

Thanks for the info on the "pounder" origin. I was always wondering about where it came from. Since we are talking about the Firefly, here is another question. When I play the Allies, which is rare, but when I do Sherman Fireflies are one of my favorites. Considering the brits got the Sherman from the US, did the US ever use the Firefly configuration for their own forces? If not, why? I would figure that if the Firefly was one of your more successful Sherman varients, the Brits would be happy to share their mod with us. Was it a case that the Easy Eights were equivalent or even better hence no need for Fireflying our own Shermans?

[CombinedArms]

<blockquote>quote:</font><hr>Originally posted by Commissar:

Considering the brits got the Sherman from the US, did the US ever use the Firefly configuration for their own forces? If not, why? I would figure that if the Firefly was one of your more successful Sherman varients, the Brits would be happy to share their mod with us. Was it a case that the Easy Eights were equivalent or even better hence no need for Fireflying our own Shermans?<hr></blockquote>

My understanding is that the Brits offered the 17-pounder to the Amis--and THEY REFUSED it! They had their own 76mm gun coming along and thought that would do the job. Then in field tests they found out their own 76 would only sometimes penetrate Panther and Tiger frontal armor. Horrors! By the time they swallowed their pride and asked for some 17 lb-ers, the Brits had decided they couldn't make the guns fast enough for their OWN needs and weren't about to give any to the Americans.

Apparently the 17 lb-er just barely squeezed into a Sherman turret, which wasn't designed for it. Maybe that was one reason the US high command turned it down. Obviously this was a mistake because the 17 lb-er was clearly the best all around tank gun produced by the western allies during the war. Apparently there was no way to wedge a 17 lb-er into a Jumbo--THAT might have been a heckuva tank. The gun was also too big for the Churchill's small turret.

Someone may be able to supply more detail, but this is the basic story.

[Slapdragon]

Actually, the Firefly was ordered by the US fairly early, at a time that the British figured the Challenger would meat all of their needs. The primary reason it was not adopted was Patton, who also put the kabosh on the M26 causing it not to be ready for D-Day (although to be fair, their was reason to stick with the M4 for D-Day because of the issue of transport.)

By the time the firefly became available (the British soon sequestered them for UK use) again it was too late. A few where acquired by the US and never issued.

[Michael Dorosh]

<blockquote>quote:</font><hr>Originally posted by CombinedArms:

Apparently the 17 lb-er just barely squeezed into a Sherman turret, which wasn't designed for it. Maybe that was one reason the US high command turned it down. Obviously this was a mistake because the 17 lb-er was clearly the best all around tank gun produced by the western allies during the war. Someone may be able to supply more detail, but this is the basic story.<hr></blockquote>

The British Firefly's ammo stowage caused the bow MG to be deleted. God forbid an American tank not be bristling with machine guns; perhaps this was why they didn't want to adopt it as well? Most Commonwealth tanks deleted the .50 calibre on the turret as well; not so the Americans who even put Ma Deuce on their 2-1/2 ton trucks and jeeps (something not done in standard Commonwealth units either).

[Andreas]

Hmm, I read in one unit history that the tankers (I think it was in 29th Armoured Brigade) gave their .50s to the motor battalion, to give them some more oomphh. They figured they would not need it. I have seen quite a few pictures of Commonwealth Shermans and M10s with the .50, but by far not all of them did have it.

[Slapdragon]

<blockquote>quote:</font><hr>Originally posted by Michael Dorosh:

The British Firefly's ammo stowage caused the bow MG to be deleted. God forbid an American tank not be bristling with machine guns; perhaps this was why they didn't want to adopt it as well? Most Commonwealth tanks deleted the .50 calibre on the turret as well; not so the Americans who even put Ma Deuce on their 2-1/2 ton trucks and jeeps (something not done in standard Commonwealth units either).<hr></blockquote>

1 in 9 US trucks had .50 cal mounts on them.

[Mattias]

<blockquote>quote:</font><hr>Originally posted by Brian:

[QB]Yes, and no. They both fired the same projectile, they did not fire the same "round". The reason why they differentiated the calibre of the weapons (17 Pdr versus 77mm) was to make it quite clear that they fired different rounds. Whilse both weapons were in fact 76.2mm calibre, and hence could fire the same projectiles, the size/shape of the chamber on the two weapons was markedly different. The 17 Pdr, originally being an artillery weapon (which was shoe-horned into a tank turret) had a long, thin, cartridge case. The 77mm, which had been designed from the outset, to be fitted inside a tank turret had a comparatively short, stubby case.[QB]<hr></blockquote>

Interesting, a situation similar to the one facing the Germans when they tried to fit their AT guns into their tanks. However unless I'm reading his book wrong it means we will have to pin another error on Peter Chamberlain (In this case in "British and American tanks of world war two).

He writes (in the 2000 edition):

"Vickers-Armstrong developed a new "compact" version of the 17pdr with a shorter barrel, shorter breech and lighter weight. Known originally as the Vickers HV 75mm (HV : High Velocity), but later called it the 77mm gun, it had a performance and penetrating power only slightly inferior to the 17pdr and fired the same ammunition."

I always assume the term "ammunition" is used with regards to the whole shell and casing package, and that in this case the same ammunition could be used in both guns.

Just for future reference Brian, are you sure your source is correct? It certainly sound like he has looked into it but I'd just like to know

M.

[Redwolf]

Speaking of the eliminated bow MG< what happend to the radio operator if his place was used for ammunition?

[Hanns]

<blockquote>quote:</font><hr> BTW is it true that the Sherman's sloped glacis was actually designed to deflect small British motorcars whilst driving on the right side of the road in Cornwall? <hr></blockquote>

I heard that Rexford was going to add an addendum to his book covering this precise problem. Seems that although plagued by inferior electrical systems the British cars aerodynamic shape proved a superb penetrator of the thin frontal armor on Shermans. I believe the Brit's were so astonished by this they started development on the 2600 lber cannon that fired cars. Apparently they had heard of the Thor and Fritz cannons that could fire a shell "the size of a Volkswagon" and thought they could build something better. Unfortunately there weren't enough Bren tripods to mount these monstrosities on and the project was cancelled

Hanns

Edited to mention that I wish my father still had his '57 XK140E

[ 01-08-2002: Message edited by: Hanns ]</p>

[Affentitten]

I think part of the issue with the USA not producing Firefly's was not wanting to dick around with their mass-production philosophy. Contracts had been awarded and lines tooled up to produce the 76mm Shermans on a massive, integrated scale, and it would have been too expensive and difficult to have changed over to produce Fireflys in anything like the numbers needed to make them a standard force component.

[Herr Oberst]

<blockquote>quote:</font><hr>Originally posted by Kingfish:

I've heard two different answers. One is the weight of the actual round, and the other is what it cost to make each round. I think the first is the correct answer.<hr></blockquote>

Soldier 1: Quick, here come the Jerries! Hand me another 18 lbr round!

Soldier 2: A what?

Soldier 1: Get with it man! War-time inflation has changed the designation!

hehe

[von Lucke]

<blockquote>quote:</font><hr>Originally posted by CombinedArms:

The gun was also too big for the Churchill's small turret.<hr></blockquote>

True --- so they redesigned the Churchill to fit the gun.

The "Super Churchill" project took a Mark VII, widened it out by 3 feet (it would have been more, but they moved the air intakes from the sides to the engine deck). Increased width = increased weight (50 tons), so they doubled the track width to 24in. Incomprehensibly, they left the original twin-six engine on board, so the re-named "Black Prince" could only make 11 mph!

Only six were built, and none saw combat.

[Slapdragon]

<blockquote>quote:</font><hr>Originally posted by redwolf:

Speaking of the eliminated bow MG< what happend to the radio operator if his place was used for ammunition?<hr></blockquote>

He was forced to run along side the tank.

Seriously, most British tanks repositioned radio equipment into the turret anyway, and gave much of the radio duties to the Commander.

[Redwolf]

<blockquote>quote:</font><hr>Originally posted by von Lucke:

True --- so they redesigned the Churchill to fit the gun.

The "Super Churchill" project took a Mark VII, widened it out by 3 feet (it would have been more, but they moved the air intakes from the sides to the engine deck). Increased width = increased weight (50 tons), so they doubled the track width to 24in. Incomprehensibly, they left the original twin-six engine on board, so the re-named "Black Prince" could only make 11 mph!

<hr></blockquote>

Why didn't they build a turretless vehicle, with the 17 pdr, the thick Churchill hull and a fate plate (as opposed to the thin Archer)?

Or for that matter, why didn't they design tank destroyers (or German-style tank hunters) or even SP AT guns after the Archer.

Did they intend to rely on US-given M10? or did they decide very early to rely only on full MBTs (like most armies did after WW2)?

[Slapdragon]

<blockquote>quote:</font><hr>Originally posted by redwolf:

Why didn't they build a turretless vehicle, with the 17 pdr, the thick Churchill hull and a fate plate (as opposed to the thin Archer)?

Or for that matter, why didn't they design tank destroyers (or German-style tank hunters) or even SP AT guns after the Archer.

Did they intend to rely on US-given M10? or did they decide very early to rely only on full MBTs (like most armies did after WW2)?<hr></blockquote>

The 17 pounder was not well suited to the interior weapon position in the Churchhill.

The M10 with a 17 pounder was just something that became available, and was never intended to be an important system. However, it turned out to be so successful with a 17 pounder that it was used many years post war.

[Redwolf]

[double post]

[ 01-08-2002: Message edited by: redwolf ]</p>

[Affentitten]

I think the main difference between the Allied and German approaches was that the Allies, and especially the USA with their massive auto production lines, tended to modify and compromise guns to fit inside a given tank body, whereas the Germans tended to build a tank body around a certain gun.

[gunnergoz]

<blockquote>quote:</font><hr>Originally posted by Affentitten:

I think the main difference between the Allied and German approaches was that the Allies, and especially the USA with their massive auto production lines, tended to modify and compromise guns to fit inside a given tank body, whereas the Germans tended to build a tank body around a certain gun.<hr></blockquote>

This is an astute observation even if I only partially agree with it.

The Sherman's 75mm gun was identified as adequate for the tasks at hand early in the design stage, as was the radial engine that would power the tank...giving the Sherman it's awkward height out of need to cram the radial within the engine compartment.

The problem came up once US forces began to actually come into combat with German tanks that outgunned them and outranged them. The tankers could see the need for a gun like the 17pdr that the Brits came up with, but the Army Ground Forces tank design staff would not alter their opinion that the 75 was adequate until post-Normandy losses proved the point beyond any doubt.

By then it was clear that the limited turret diameter of the Sherman series would severely hamper gun accomodation. The 76 fit fairly well, but the 17pdr required a box to be cut into the back of the turret to make things work and give the loader enough room to load rounds at a decent clip.

The Pershing had a larger diameter turret ring designed into it specifically to accomodate the 90mm gun that was by then identified as the minimum weapon needed on the battlefield to cope with current German (and Russian) designs.

In the end, tank designers always have to balance firepower, horsepower (manouverability/reliability) and survivability in their designs. Once the design is frozen, however, it becomes much more difficult to alter the equation that originally derived the design (e.g. the Sherman Jumbo had a relatively low reliability compared to the lighter versions, trading off speed/reliability for survivability.)

German designers did seem more willing to step outside the box, and come up with aggressive solutions to their challenges than did US tank designers who were on the whole severely conventional. The US Army Ground Forces, given such a variant to assess, would have picked to death a turretless TD/SPG design in 42-44... but the Germans implemented one (several, actually) and capitalized upon it's good points with excellent results. By late '44 and '45, the US designers had seen the light and started to look at some turretless designs for super-heavy gun platforms...a day late and a dollar short, as they say.

[Affentitten]

But in my first post I was trying to point out the fact that it was far harder to accommodate change in US production, even when mistakes like the 75mm were uncovered. The sheer scale of US production and its farming out to so many producers made incoporating change very difficult, and the very nature of the mass-produced and interchangeable fighting formations made providing different models to different units impractical.

German industrial production tended to be a bit more bespoke, not to mention the fact that they were desperate enough to seek outside the square. I guess the Americans were comfortable in the fact that they were going to win on numbers and that there would always be a third Sherman to pick off the lone Panther that had just nailed two of his buddies.

[Jagdratt]

<blockquote>quote:</font><hr>Originally posted by Michael Dorosh:

The British Firefly's ammo stowage caused the bow MG to be deleted. God forbid an American tank not be bristling with machine guns; perhaps this was why they didn't want to adopt it as well? Most Commonwealth tanks deleted the .50 calibre on the turret as well<hr></blockquote>

Any information on how common it was for a TC to engage hostile targets (to distinguish between targets that can and cannot fire back at you) with the hatch mounted .50 cal? It seems like a very exposed firing position, on top of an already tall tank. I note that German AFVs that commonlly had top mounted MGs had a small splinter shield. Were those shields actually capable of stopping an infantry rifle/SMG round, or were they more for psychological effect?

[Redwolf]

<blockquote>quote:</font><hr>Originally posted by Jagdratt:

Any information on how common it was for a TC to engage hostile targets (to distinguish between targets that can and cannot fire back at you) with the hatch mounted .50 cal?

<hr></blockquote>

Apparently that wasn't often. When I come around .50cal shootings, it is usually on targets that don't fire back.

<blockquote>quote:</font><hr>

It seems like a very exposed firing position, on top of an already tall tank. I note that German AFVs that commonlly had top mounted MGs had a small splinter shield. Were those shields actually capable of stopping an infantry rifle/SMG round, or were they more for psychological effect<hr></blockquote>

That is the "forward" MG in CMBO terms, found on StuGIII (not late) and some halftracks. It is certainly capable of stopping small arms rounds. I have to look up how thick it actually was, it might even be capable of stopping .50cal.

The Germans stopped using it because they found that once enemies were in machiengun range, you could bet that more of them show up on angles that are not covered by the shield.

[Conscript Bagger]

<blockquote>quote:</font><hr>Originally posted by Jagdratt:

Any information on how common it was for a TC to engage hostile targets (to distinguish between targets that can and cannot fire back at you) with the hatch mounted .50 cal? It seems like a very exposed firing position, on top of an already tall tank. I note that German AFVs that commonlly had top mounted MGs had a small splinter shield. Were those shields actually capable of stopping an infantry rifle/SMG round, or were they more for psychological effect?<hr></blockquote>

One of the unfortunate abstractions in the game is that an unbuttoned tank commander is assumed to be peering out just over the rim of his hatch and is thus fairly difficult to hit with small arms/shell fragments, but at the same time has the ability to fire the AAMG as if standing on the rear deck.

[/whiny bastard mode]