Deadly Rivets?

I have been wondering about the deadly rivet thing. Was it a myth? Seems doubtful that a rivet could be punched through to the inside of a tank by a rifle caliber bullet.

 

I saw something recently about the rivets being an internal projectile issue with the Lee/Grant design.

 

Oh I see it mentioned all the time too about any armored vehicle with riveted or bolted armor but I've never seen a picture of an empty rivet hole on a tank, even ones that have been blown up

 

Neither have I.

It could be one of those very common scenarios where writers pick up a previously published assertion and repeat it without verification.

 

I think it's plausible as a rivet is effectively two domes held by a link in high tension. Release that and effect is considerable! So knocking off the outer dome and the inner dome is released even before considering the possible kinetic energy of the impact from a bullet, shell fragment etc. Warped ships plating could have a similar effect.

 

"Rivets popping from the tank scourged the neighbourhood like machine gun bullets"

A Sticky Tragedy: The Boston Molasses Disaster | History Today

 

I would think rivets popping is related to the mechanical stresses set up on metal plates when they are struck by external source,the stresses are then applied to the rivet core which may become elongated and fail...the same result although not to the same degree might be met if plating was ruptured and the projectile then struck plating as it circulated under force around a confined space.Stresses may also be quickly set up on rivets if the plate is heated up by impact of a projectile local local to the rivet.

Takes me back to a pilot I was aware of whose nickname by airframe mechanics was "Pop Rivet"....I was told by his FE that he was an accomplished pilot but he drove a Lincoln bomber to the limit of its flying envelope (G limit),so much so that airframe panel rivets would be overstressed and pop....to be revealed during an After Flight Inspection.

 

This I've seen mentioned a lot too as fact in many places but with few, if any, direct sources backing it up.
References to the early US light tanks and the M3 medium suffering from this issue are very frequent but never sourced.
Archive Awareness : Light Tank M3: America's First Thousand

has this to say:

and then there's this oblique mention
An Assessment of the M3 Stuart Tank

But not mentioned as a major issue or cause of casualties

The book Rude Mechancials which showed up recently on this forum under 'bad history" makes this claim on page 109 : "The official report on AFVs in the Mediterranean Theatre tells of rivets 'flying around like bullets' when a tank was hit" However no source or reference citation is provided and no indication of what report this actually is.

Finally in the book British Tank Production and the War Economy by Benjamin Coombs this sentence appears on page 60: " Furthermore ,the use of cast armour eliminated the danger of rivets being forced into a tank's interior to endanger the crew when the tank was hit" This is actually sourced to page p 71 of The Business of Tanks 1933 to 1945 by J Macleod Ross. Not a book I'm familiar with but may be worth a look if someone has access to a copy!

 

Perhaps the story stems from a cavalry version of a naval tradition ?

"This,Trooper is the golden rivet. If it's hit by a bullet it will fly out and kill you. Now stick your head inside the turret and have a look at it..."

 

There are definitely primary source reports of this occurring. I've got a lethal one reported for a Crusader in 1942. It was a rare event, but it did happen. I'll see if I can rustle it up sometime.

I can also confirm that "Rude Mechanicals" is a remarkable book in that I don't think there is a single sentence in it that is factually correct or not preposterously exaggerated.

As for the "The Business of Tanks 1933 to 1945", this was actually by George MacLeod Ross who was a minor player in tank development before and during the war. He was the engineer who oversaw the creation of the Sherman Firefly, and was a crony of the Director of Artillery, Campbell Clarke. As far as I understand it "The Business of Tanks" was a private paper and was not commercially published, but I'm happy to be corrected on that point.

 

Business of Tanks, Ross - AbeBooks

Looks like it was released commercially in 1976 by Arthur H. Stockwell Ltd. Might have to pick it up as there are some cheap copies available.

 

Learning more about rivets than I'd ever thought I'd need
A couple more things I found in my searches:
The Marysville Tribune from Marysville, Ohio on October 18, 1941 · Page 1

Contains the following news piece (please excuse the garbled text pieces the site messes up some of the text, didn't feel like paying to access the site):

My admittedly brief searches haven't found another source for this or the orginal study on armour in France 1940 that is mentioned in the article. Tantalizing mention.

and on a different rivet related topic that came up in searching:
HMS Formidable: Kamikaze, 9 May, 1945

 

It says:

Relative sizes of rivet and projectile probably come into this. You might believe a rifle calibre bullet could pop a rivet on a British Light Tank, but it seems less likely on a Lee.

Orwell's post aligns with my thinking that the issue was perhaps more to do with the effects of HE shells bursting on - but not penetrating - rivetted plate which might otherwise have been survivable.

 

I've actually got copies of some of MacLeod Ross's private papers (aren't I fancy, eh?), so it would be interesting to see how objective his book is.

In the mid-thirties, he was the right hand man to Campbell Clarke, who was at that time the leading tank designer within the British Army. The experimental A7 was the product of the two men. In late 1936 Clarke (apparently reluctantly) became the Director of Artillery, while at the beginning of the war MacLeod Ross was sent over to Washington DC as part of the British Supply Mission, where he had a technical liaison role. He returned to the UK circa mid-1943, where he became involved in the Firefly, and gun mountings in general.

Clarke and Ross were generally on the sidelines during the crucial periods of tank design, the key drivers of tank development between 1937 and 1945 being, respectively, Giffard Martel, W.A. Robotham, and Claude Gibb. This was not the kind of marginal position they would have expected to be in when they were working together in 1936.

 

Might be of interest.

 

I've found a few anecdotes about crew members wounded by flying rivets after a non-fatal strike from an AP round. The first was in a Stuart tank in the Philippines and the second reported by Japanese tanker. Both were penetrating wounds.

Rolling Thunder Against the Rising Sun: The Combat History of U.S. Army Tank
By Gene Eric Salecker

World War II Japanese Tank Tactics
By Gordon L. Rottman, Akira Takizawa

 

Below is the extract from the report on the Crusader tank that I mentioned above. The extract is from Middle East AFV Technical Report No.2, of 9th January 1942, by Colonel William Blagden.

The author refers to bolt heads flying off, but these must have been rivet heads, as the only armour bolting on the Crusader was external.