I need some help with gun emplacement specs.

[Michael Comer]

I had a very good meeting with the City of New Madrid today. They are behind our effort all the way and will be providing materials for us to build the gun emplacement. But, to give them an idea of what we might need I have to have an estimate of the amount of dirt needed. I've been looking for some specifications on fieldworks to use as an example but have not come up with anything.

Does anyone know or have information about sizes of say a 2 gun field emplacement? The city is cleaning out ditches and has plenty of good, clean dirt right now and the city manager would like to know how much is needed so that it can be set aside. I don't need exact numbers but I am looking for some sort of lay term estimate that I can give him such as yards of dirt, how many dump truck loads etc.

Any help from you field fortification fans or engineer types would be helpful.

[Jimmayo]

Re: I need some help with gun emplacement specs.

Been a long time since I was in it but I think the Official Records map book has some fortification drawings included. Not sure they are what you want but the book should be easy to find to check them out. The thing about field fortifications was they tended to get larger if they were used for an extended time. Should also be some pictures in the LOC.

[gtg625a]

Re: I need some help with gun emplacement specs.

You have a couple of options in terms of construction that I would need to know before giving an earthwork estimate.
1) When you say field work are you saying a work for a field piece, but more or less preprepared, or do you mean a work for a field piece that is more of a hasty position? (e.g. a Vicksburg type work or an Atlanta Campaign type work)
2) Is it your intention to dig in and build up the parapet or to construct a parapet and ditch from the ground up without disturbing the original soil?
I will have follow-up questions depending on the answers.

Regards,

[erik]

Re: I need some help with gun emplacement specs.

Michael,
Reference to Captain Grafton' s "On Camp and March" 1854, gives a total volume of 137.5 cu yds to for a yard of parapet. This soil would normally be taken from the ditch when it was excavated, thrown up and tamped to form the various shapes. This would be a standard parapet. A gun emplacement would require more as gun platforms and ramps are needed.
If it is Fort Thompson you are replicating a bit of plan reading with a scale and simple geometry will give you a usable volume.
From my understanding you have soil with a reasonable angle of repose and compaction.
You need a good profile, drainage and revetment.
I hope that this helps.

Erik Simundson

[Michael Comer]

Re: I need some help with gun emplacement specs.

The emplacement will be for two guns and will be more of a permanent fortification. It will be in the general vicinity of where Ft. Bankhead was built, a smaller installation on the north side of the town. Since we cannot build this thing in the course of a single event, the city will put the dirt in place for us so the basic work will be there already. We will cut out the embrasures and use posts and boards to shore up the inside and build gun platforms. This should be able to be accomplished. Some dirt may be moved also. I've got 10 dump truck loads of dirt available.

[erik]

Re: I need some help with gun emplacement specs.

Michael,
what is the volume of each truck?
You should have a trace laid out of the forward edge before they dump. This is a simple task done with a compass and a few stakes.

Erik Simundson

By the way what guns are you planning for? Are they in barbette or embrasured heavy guns?

[thomas aagaard]

Re: I need some help with gun emplacement specs.

if the parapet is to stand up to 12pounders it need to be 10-12 feet think.
If on flat ground it need to be 7feet 6inches high. (so horsemen can not fire over it.)
If it is on higher ground than what the enemy can site artillery on is can be 5-6 feet tall.

Numbers are from "hand-book for active service by Egbert L. Viele - from march 1861

I was doing some match, but need to know a few things.

Do you plan the "banquette (where the men/gun stand) to be raised as it should be.. or do you plan to have this a ground level?
How much length do the gun need for it self+recoil?

model I put together in SketchUp
With a 4feet Banquette that is raised as the book writes it should be.
It need 102 cu feet pr. feet of earth pr. feet of the length of the line.
fieldfortification.jpg

This is naturally just math... I have no practical experience with civil war work.