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Clam Mine
- Thread starter spotter
- Start date
Spotter I looking this magnets to my clam mine. You got it yet? I would be very grateful for your help.
Below dimensions my clam mine.
I dont think i have any left but i will have a look for you
allan
The clam is a Mine/demolition charge which is attatched to the target by strong magnets.It contained 8oz of HE.IT could penetrate 25mm of plate metal and was capable of cracking engine blocks,and bending rail track.The Mk1 was made of tinned steel,The Mk2 and Mk3 were made of bakelite.A "L" delay was used to detonate this device
This image shows the clam as found
Hello!
Do you know, when first Clam began to used in British Army?
Maybe you have old manual on thus mine?
I asked some question, but nobody answered me :tinysmile_cry_t: http://www.bocn.co.uk/vbforum/clam-mark-1-t76041.html
Clam
Production of the bakelite Clam started at the end of April 1940 (5 pence each by De La Rue of 69 grenade fame) but their issue was confined to saboteur groups, Independent Companies (Commandos) and some to Auxiliary Units. Directorate of Ammunition Production (Ministry of Supply) took over production from MD1 in 1943 when the Clam (Mark III version) was more generally available to the Army. Large stocks of the Mark IIIs were shipped to Russia and were copied (maybe still are?) for SF use.
About 12.5 million Clams were made in the UK.
The first pattern (see photo) was of metal, rather than plastic, construction with floating magnets. The second was plastic and use fixed horseshoe magnets. The Mark III (actually called Mark II by MD1 at the time of design) was deeper and reverted to the use of floating magnets.
Production of the bakelite Clam started at the end of April 1940 (5 pence each by De La Rue of 69 grenade fame) but their issue was confined to saboteur groups, Independent Companies (Commandos) and some to Auxiliary Units. Directorate of Ammunition Production (Ministry of Supply) took over production from MD1 in 1943 when the Clam (Mark III version) was more generally available to the Army. Large stocks of the Mark IIIs were shipped to Russia and were copied (maybe still are?) for SF use.
About 12.5 million Clams were made in the UK.
The first pattern (see photo) was of metal, rather than plastic, construction with floating magnets. The second was plastic and use fixed horseshoe magnets. The Mark III (actually called Mark II by MD1 at the time of design) was deeper and reverted to the use of floating magnets.
Attachments
Jeff,
The 3 for PE is on a Blue ground. The Green and Black bar is for TNT based filling. The code 3 on this combination with yellow edging seems to indicate that it is filled TNT/CE 55/45. A code of T.N.T.3 would indicate RDX/TNT 50/50.
I have attached a photo of the botttom of the Mk.I showing the floating magnets and stencil markings.
Attachments
Thanks Anders, nice to see the MD1 inspection marks.
Its a perfectly correct combination of course but Stuart Macrae would be turning in his grave if he saw the Time Pencil in the Clam rather than the 'L' delay - an American time pencil at that. The SOE preferred the Time Pencil over the 'L' Delay but then their techies designed the Tim Pencil.
Its a perfectly correct combination of course but Stuart Macrae would be turning in his grave if he saw the Time Pencil in the Clam rather than the 'L' delay - an American time pencil at that. The SOE preferred the Time Pencil over the 'L' Delay but then their techies designed the Tim Pencil.
Yes I am sure he would. :tinysmile_hmm_t:
But unfortunate I do not have an LDelay :tinysmile_cry_t:
Hi. Here's a data sheet I put together on one of my clam mines. Probably of most interest is the wooden dummy fuze. This is original to the mine, but I am not sure if it was just a shipping plug or actually a training fuze. This mine was one of several found in an old army dump many years ago. None of the mines were stenciled and several had the wooden fuzes. Cheers
Attachments
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Rectifier
The wooden 'fuze' is what is called a rectifier (also called a plug or a pin on MD1 literature). The early marks of the Clam were field filled with a plasticised explosive and the rectifier, which is the shape of a No 9 'L' Delay Switch, was inserted to make suitable shaped hole for the 'L' delay and detonator (ie the fuze). The prefilled Mark IIIs still had the rectifier. The photographs in your datasheet show Mark II clams - they are slightly less deep than the Mk III and use fixed horseshoe magnets.
The wooden 'fuze' is what is called a rectifier (also called a plug or a pin on MD1 literature). The early marks of the Clam were field filled with a plasticised explosive and the rectifier, which is the shape of a No 9 'L' Delay Switch, was inserted to make suitable shaped hole for the 'L' delay and detonator (ie the fuze). The prefilled Mark IIIs still had the rectifier. The photographs in your datasheet show Mark II clams - they are slightly less deep than the Mk III and use fixed horseshoe magnets.
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Hi Fragman
I think you actually have a Mk II clam there. Also, I am told, known by MD1 as a Mk 1 Plastic, just to confuse the issue. Mark III clams are deeper, between 38-40mm and have single magnets at each end. My example which appears identical to yours only measures 30mm deep.
These clams were often of the "self fill" type and the user would pack them with whatever plastic explosive available. The wooden "dummy fuse" is for use as a rectifier to push a hole in the filling to enable you to fit your time pencil when required.
Hope this helps
Regards, Switch
I think you actually have a Mk II clam there. Also, I am told, known by MD1 as a Mk 1 Plastic, just to confuse the issue. Mark III clams are deeper, between 38-40mm and have single magnets at each end. My example which appears identical to yours only measures 30mm deep.
These clams were often of the "self fill" type and the user would pack them with whatever plastic explosive available. The wooden "dummy fuse" is for use as a rectifier to push a hole in the filling to enable you to fit your time pencil when required.
Hope this helps
Regards, Switch
