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WW1 Practice Bomb

Millsman

Well-Known Member
Premium Member
Recently bought this small bomb. The seller said it was a RFC 3lb practice bomb.

Photo below.

Anyone confirm this?

DSCN1919.jpg
 
John . More likely RAF practice bomb from the 1920's . We've had this query before & they have a few examples [or did have] in the museum at Hendon . Mike .
 
That's great. A perfect match. Very many thanks.

Only question. In 1918 bombers were getting larger as were the bombs. So where does a 3lb bomb fit in? It's more like a cluster munition, or was it for hand throwing in initial bombing training?

John
 
Thanks Tom.

I would have thought the wind would have a significant effect on drift for a 3lb bomb as opposed to a 250 or 500 bomb for a bomb dropped from say 5,000 feet, unless of course these were only used in ground attack simulations with the bomb being dropped from low level.

John
 
Some of those bombs are dated, and the earliest I have seen is 1915. Then, and even until 1918, any significant wind was likely to have more effect on the machines than on anything dropped from them. The 3lb practice bombs no doubt sufficed to simulate the flight path of things like 112lb HERL and larger siblings until the end of the war.

Even today 10kg (22ish lb) practice bombs are used to simulate the flight path of 500kg dumb iron bombs, at least from some very recent film I have seen of RAAF
practice bombing runs.


Tom.
 
What do you make of the lack of a suspension ring? That was what made me think it might be hand dropped (or a canister based munition).
 
Small HE bombs were hand dropped in the early days of the air war and it would have made sense to have had a hand dropped practice device, for which this small bomb may have been the design*. However, it also has the circumferential groove around the body (probably close to the centre of gravity), and usually there is a small hole towards the rear of one of the fins, both of which - without getting too speculative - would facilitate mounting with a remote release.

The layout shown in the drawing posted by MINENAZ16 has similar features to the later RAF 11.5lb practice bombs - a solid nose, thin-walled back end for a pyrotechnic marker, and a simple nose-mounted striker held safe by a split pin. The structure is not really that of HE, antipersonnel, or incendiary, all of which have their own design characteristics, but it would be nice to find a drawing describing Method of Filling.


*The markings on a relic 3lb bomb in my possession a long time ago were the year 1915 and the letters W D either side of a broad arrow. I cannot recollect any other markings.



Tom.
 
I think you may be right about the groove in the cast iron body. It would facilitate a pincer like release mechanism as you say, it's in the right place at the COG. My example doesn't have the hole in the fin, nor visible markings. The fins do have some surface rust so I'll try to gently remove that and see if there are any stamps.

Looking at the diagram I suspect the charge detonator was some long tube like device with a shotgun type cartridge at the end that was inserted first. The end cap keeping it in place and just popping off when the charge ingited. So they were probably reusable, thought the nose cap looks a bit fragile.

Lovely to own such a nice item.
 
Three more, all have the small hole in one fin, plus an eg that is exactly two inches longer but is otherwise identical.
Second pic is of a baby incendiary bomb that was, when I first saw it, complete with its tinplate fins and sliding det holder. By the time I finally liberated it, they had lost both the fins and the internal det holder. Bit uncommon, so unlikely, but does anyone have a spare set of fins, pse?DSCN0498[1].jpgDSCN0497[1].jpgDSCN0497[1].jpg

Thanks,
Alan1
 
Small HE bombs were hand dropped in the early days of the air war and it would have made sense to have had a hand dropped practice device, for which this small bomb may have been the design*. However, it also has the circumferential groove around the body (probably close to the centre of gravity), and usually there is a small hole towards the rear of one of the fins, both of which - without getting too speculative - would facilitate mounting with a remote release.

The layout shown in the drawing posted by MINENAZ16 has similar features to the later RAF 11.5lb practice bombs - a solid nose, thin-walled back end for a pyrotechnic marker, and a simple nose-mounted striker held safe by a split pin. The structure is not really that of HE, antipersonnel, or incendiary, all of which have their own design characteristics, but it would be nice to find a drawing describing Method of Filling.


*The markings on a relic 3lb bomb in my possession a long time ago were the year 1915 and the letters W D either side of a broad arrow. I cannot recollect any other markings.



Tom.

Tom,

You may be amused to note the entry in the Research Department's drawing register for the drawing shown by MINENAZ16. Even scientists in Woolwich Arsenal had trouble identifying this practice munition unless of course it really was dropped by a German Airship!


RD DrawingRegisterPage.JPG
 
Thank you, Norman. That is excellent, especially as I have found absolutely nothing regarding contracts for practice bombs of any type.

Considering the large objects (HE and incendiary) the Germans normally dropped, it would have been an odd device to drop from an airship. Maybe it was a pathfinder Zeppelin.



Tom.
 
Thanks Tom

I'm due to visit the RAF Museum in 3 weeks time so will send them a message to see what documentation they have. Especially in the light of you not finding any contracts for their supply.
 
Hi Millsman would it be possible to post the dimensions of the striker and shear wire holes please
thanks Tom
 
Hi Millsman would it be possible to post the dimensions of the striker and shear wire holes please
thanks Tom


The Striker is 45mm / 1 3/4" Long. The wire at present is 1mm thick and the hole 1.5mm. I cannot guarantee the wire is original.

Here's a photo of the bomb dismantled.

DSCN6229.jpg
 
On advice from Millsman, I have bought my one of these into the warm, from its previous location in the garden!:tinysmile_hmm_t:
 
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