29mm Spigot Mortar Blacker Bombard tail and drum fins measuerments


Hi, I have been a member here many years ago when i was into .50 cal bmg ammunition and 2" mortar propellant cartridges but have lost track over the years and have long forgotten my username etc and memory along with it as i am getting older.
I have just recently discovered a 29mm Blacker Bombard Spigot mortar emplacement near where i live, funny enough not that far from where the inventor Lieutenant Colonel Blacker lived, near Liss Hampshire UK about 2 miles away. I also acquired a practice 14lb head filled with concrete but missing its tail and drum fin. I was reading the manual which stated that after a few firings of both practice rounds that the tails and especially the drum fins get damaged and bent and can be straightened out to be used again or the fins can be replace from stores as spares for reuse hence the circlip on the base of the tail.
I was also interested that the propellant cartridge used with Spigot ammunition is made from a Masden 20mm cut down round, not sure if this is true or is the cartridge is purpose made or improvised. What i am after is D.W.S notes on the 29mm Spigot ammunition showing the dimensions and sizes of the tail and drum fin as i would like to make a new one up for my newly acquired 14lb head as most fins now are severely corroded being made of tin like the P.I.A.T design. Can anyone help.


29 mm Blacker Bombard Spigot Mortar- Home Guard Weapon, 1944 Britain.pdf (5.1 MB)





Thanks bdgreen, have seen the BOCN posts but i didn’t have the 1944 book which was very interesting. I was right about the Madsen launcher cartridge. Just need to find measurements for the tail and drum fins, have asked on the BOCN forum but it seems that most members have sold on their rounds. I know that there are ammunition drawings as i have seen them for 2 pounder star shells showing measurements which includes the type of colours and markings etc. Have asked the IWM and the records office at Kew, i wonder if there is anywhere else i could try. I did have someone help with measurement but it was with builders tape measure dangled in front of his tail and fins, helpful but not helpful, need to be much more accurate that that having an engineers background.