M-4 Sherman composite hull?

It's times like this where we really miss Shermanfreak's contributions to the forum.

where is sherman freak anyho?

Good question. I do know there was the belief by some that the rounded countours of the cast hull provided better protection than the welded varieties by allowing the shots to more easily skip off. So I think the composite hull was intended to provide the advantages of the cast hull while allowing maybe some of the simplicity of the welded hull. As far as manufacturing ease, who knows. According to squadron's Tiger book, the Tiger II was easier to build than the Tiger I. That runs counter to what I would have intuitively guessed.

On the other hand, I too have always wondered about the composite hulls, but my question is why did they retain dry ammo storage? I've never read a good answer on that one.

When it comes down to it,it depends on the manufacturers of these tanks.During the war the U.S.Army used serveral manufactures to make there equipment.One would have the fialciltys for casting and the other would use welding.So to get more of them out in the field,in this you would have to check the manufacturers on these tanks.I know that GM and Chrisyler manufacture Shermans.Digger

Looks like this may be one of those "never to be answered" questions.
I was thinking the composite hull was considered a late production, so the biggest advantage would be to get the larger hull hatches. Again that could be accomplished by using the same hull as the M4A3.
Never thought about the dry ammo storage, but that is a very good question as well. Now I have two points to ponder.
Thanks for the opinions. I'll just hang loose to see if any one else has any input.
Regards,
Joe

http://www.network54.com/Forum/thread?forumid=212524&messageid=1092348608

Looks good...its a Canadian Firefly but on the Cp hull so should help a bit

AJ

It's my understanding the composite hull was used for the late production M4, not the M4A3. As to why? I've no real idea except for the idea already mentioned that it was done to speed up those facilities that couldn't cast large pieces.

Well, now I'm a bit confused.
Ali1kj,
Nice pictures, but how does that do anything as far as answering my question? Did I miss something in the post or the pictures and posted responses?
Spamicus,
That was basically my question. Since the M-4 and M4A3 were pretty much identical throughout their developement, why make a composite hull when they could have used the M4A3 late hull for the M-4 late?
Regards,
Joe

Robert (Shermanfreak) is the real expert on shermans, but the M4A3 had a different engine from the M4. That's why M4 and M4A1's were often in the same unit, they had the same mechanical equipment. I realize I'm not answering your question because I don't really know the answer. Like has already been mentioned, I think it may of had something to do with streamlining production, though I can't figure out how.

Spamicus,
My apologies, I thought perhaps I was misunderstanding your answer or you might not be understanding my question. Sometimes (?) I don't phrase thing as clearly as possible.
I still can't figure how taking two completely different body styles and mating them can steamline production, so I guess we are in agreement on that count.
It may remain one of life's great mysteries.
Regards,
Joe

i have worked on restoring a composite hull 105 sherman (one of 75 made) and the research i did on it i found that the reason the made the composite hull is that cast steel has better tensile strength that rold steel. so they cast the front to get the advantages of the cast hull and the faster production of the welded hull

Interesting discussion. The story of why the composite is kind of convoluted. What's really interesting is the fact that NONE of the different early hulls were the same until the 1943 composite hulled "Ultimate" design. All of the hulls had different component parts. the hoods on the M4, M4A3, and M4A4 all had different drawing numbers and were different parts. The Ultimate design was being developed to streamline production.

All of the late armament prototypes (i.e. 76mm, 105mm) were built on composite hulls. The 47 degree rolled plate hull front seen on all of the welded up hull models of the Ultimate design that were put into production (M4 105mm, and M4A3) was a quick design change done at the last minute because the cast fronts did not do as well in ballistic tests, the rolled plate hulls were quicker to make, and they did not use as much casting industrial capacity, which was in extremely short supply.

The cast armor was thought to be better, and that theory was stuck to by Army Ordnance until the M1 Abrams.


osiveon, where did you work on the 105mm composite? That sounds like the prototype that used to be at Warren.

Mike Canaday

its at fort wayne in Detroit MI
they also have a M19A1?
and a M114

All that I can tell you is that the Composite Hull was the late M4. The M4 had a real problem with the "hatch box extensions" sticking out of the glacis plate causing weak points. Put the late M4A1 front on a factory M4 and voila, you have a safer Sherman.

Why was it done? For the same reason that we didn't build a different (better armored) tank until late. Assembly lines, supply, and shipping. Logistics...logistics...logistics. It was probably easier to modify an M4 plant to place the cast front onto their existing design than to make an M4 plant into an M4A3 plant.

Need proof (or an argument for it)? The Composite Hull shermans still used the dry ammo bays and thus added applique armor.

This is all in the Squadron Sherman book. I have another source if I can find it in my room full of model stuff.

Hello to All,
Well, all I can say now, is that I'm thoroughly confused.
I've seen a picture in the Hunnicutt book (since this original post) that shows an M-4 105mm in the same body as a late M-4-A3. If they used it for that, why not just put the late M-4 in the same body?
The more I learn the less I know. Thanks to all for the input.
Regards,
Joe