Post by hawkeyes on May 27, 2020 6:56:37 GMT -7
For some time I've been planning the build of a full size Coehorn 4.4" bored land service mortar, which was the smallest sized piece used in the range up to 13". I personally find mortars appealing due to their simplicity in design and the very rewarding BOOM amplified by the large bore.
I've taken my dimensions directly from the wonderful document concerning British artillery here...
sha.org/assets/documents/British%20Smooth-Bore%20Artillery%20-%20English.pdf
Let me be clear in my statement that this is NOT a 100% historically accurate representation of this particular piece. I absolutely do not have the necessary funds nor toolkit to undertake the task of producing an authentic mortar. However, I do have the ability to safely recreate the piece you will eventually see. I am trying to "emulate" as close as I can to the original with what materials I have available.
My dimensions are of those mortars described from 1760 to 1850, which is approximately 12.5" in length and a bore diameter of 4.5".
One notable difference that isn't talked about between cannons and mortars is mortars are chambered. Which in essence was done to eliminate the weight of the projectile directly sitting upon the powder charge. This would compress the charge causing ignition issues and ultimately be extremely unsafe potentially causing a misfire while loading.
My chamber is a tad smaller than the dimensions listed and planned:
Chamber diameter of 1" and a length of 2 3/8". This came out to be an exact 400gr. charge.
I can estimate my weight is again a very close approximation to the originals at 80lbs which is notable in the text to have changed many times.
The image is a representation of what I'm trying to replicate in terms of the bed. Originals were made from oak and I intend to do the same. Trunion starps and all hardware I'll be forging.
Having my dad weld the chamber and trunion up today as my welder isn't able to safely handle the required amount of heating and weld penetration needed to maintain structural integrity. Images will be posted as progress is made!
I've taken my dimensions directly from the wonderful document concerning British artillery here...
sha.org/assets/documents/British%20Smooth-Bore%20Artillery%20-%20English.pdf
Let me be clear in my statement that this is NOT a 100% historically accurate representation of this particular piece. I absolutely do not have the necessary funds nor toolkit to undertake the task of producing an authentic mortar. However, I do have the ability to safely recreate the piece you will eventually see. I am trying to "emulate" as close as I can to the original with what materials I have available.
My dimensions are of those mortars described from 1760 to 1850, which is approximately 12.5" in length and a bore diameter of 4.5".
One notable difference that isn't talked about between cannons and mortars is mortars are chambered. Which in essence was done to eliminate the weight of the projectile directly sitting upon the powder charge. This would compress the charge causing ignition issues and ultimately be extremely unsafe potentially causing a misfire while loading.
My chamber is a tad smaller than the dimensions listed and planned:
Chamber diameter of 1" and a length of 2 3/8". This came out to be an exact 400gr. charge.
I can estimate my weight is again a very close approximation to the originals at 80lbs which is notable in the text to have changed many times.
The image is a representation of what I'm trying to replicate in terms of the bed. Originals were made from oak and I intend to do the same. Trunion starps and all hardware I'll be forging.
Having my dad weld the chamber and trunion up today as my welder isn't able to safely handle the required amount of heating and weld penetration needed to maintain structural integrity. Images will be posted as progress is made!
