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40 Lb Bomb Demo

Thank you Harry and betwwen us :tinysmile_hmm_t: heel mooi exemplaar

Chris
 
I think that 290 mm could be a typo, and that it has to be 29 mm. This because it is similar in principle as the 29 mm Spigot Mortar Bomb (Blacker Bombard). The Bomb Demolition No. 1, 40 lb. Mk I & II have a diameter around 229-231 mm and has a total length of 637-638 mm. So nothing in the area of 290 mm. Or maybe the outside diameter of the barrel is 290 mm. Who has a Churchill AVRE??

Antoon

Schermafbeelding 2021-11-28 om 14.09.59.png Churchill AVRE.jpg
 
I think that 290 mm could be a typo, and that it has to be 29 mm. This because it is similar in principle as the 29 mm Spigot Mortar Bomb (Blacker Bombard). The Bomb Demolition No. 1, 40 lb. Mk I & II have a diameter around 229-231 mm and has a total length of 637-638 mm. So nothing in the area of 290 mm. Or maybe the outside diameter of the barrel is 290 mm. Who has a Churchill AVRE??

Antoon

View attachment 173486 View attachment 173487


This has come under some scrutiny recently, I'd like to claim it's due to my book, but....

So, as they say in Dragnet 'Just the facts!':

1: Bomb is 9in across. Here's me measuring the bomb at Mod Kineton:
DSCF4869.jpg

2: The Loading tray on the Petard has raised strips to support the bomb in the tray. You can see them in this image:
https://commons.wikimedia.org/wiki/...0lb_bomb_can_be_seen_on_the_right._H38001.jpg

It has been suggested that the 290mm measurement is for the width of the loading tray, not the raised parts. So a friend went and measured one, and gotten the measurement of 241mm.

3: The best hypothesis that anyone can come up with is that it's tied to the calibre of the spigot, and someone simply misplaced the decimal, and it stuck.
First option was it was done officially to prevent confusion in shell sizes for logistic reasons, much like the '95mm Cs howitzer or the 77mm tank gun). Trouble is every primary document myself and at least two other friends have seen has described it as a 40lb demolition charge No1. Although documentation of the 30lb No2 is vastly rarer, the same applies here.
That leads us to a post war author or museum, and some one was reading a doc, and saw '290mm', when the document actually said '29.0mm'. If this was due to faded print or carelessness we don't know, nor do we know when the measurement first got attributed.

For what it's worth I suspect this last point is right. It has happened before, with the FV215a and FV215b. Only difference there is we know who the author was, as we found his book (although I forget his name at current).
 
Just a side note there was one of these used as a carpark marker at the royal engineers museum in Chatham many years ago flying dustbin springs to mind.
 
They fired these against the Atlantic wall at Hankley common, i suspect there are spigot brass littered there and remains of tail units from the blast just like the PIAT bomb does.
 
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