13-inch Seacost Mortar
American Civil War
The 8-inch and 10-inch siege mortars had a maximum ranges of 2,225 and 2,064 yards, respectively, and the 13-inch seacoast mortar had a maximum range of 4,300 yards, but their effective ranges were much shorter. For the 8-inch siege mortar at a range of 800 yards, about 50% of the shells would fall within a 50-yard radius of the target. With the 10-inch siege mortars at 875 yards, about 60% of the shells would fall within a 40-yard radius of the target. The 13-inch seacoast mortar could be expected to be more accurate.
Mortars typically used spherical shells, with both timed and percussion fuses.
The 13-inch seacost mortar shell weighed 197 pounds (90 kilos) and the mortar itself weighed 17,120 lbs (7,800 kilos)!
Here the mortar with my Captain of the 1st Connecticut Heavy Artillery Regiment to give the piece a scale reference.
This is the 13 inch mortar by Battle Gear Toys(BGT).
It comes unassembled but assembly is very simple. I weathered the various parts and painted the barrel a darker color, including the part that is moulded as part of the carriage to make it stand out.
Also drilled out the small hole in the carrying hook on top of the barrel.
All the parts shown come with the mortar, except the metal things which do come but I replaced with these made from wire and the shells.
It took a while to find the shells and eventually found them in my own home! Used 2 ¼ inch pool table balls! I first sanded them to remove the smooth varnish and then painted with many varios colors with the airbrush. Added some dry-brushing also. The size is PERFECT for this mortar and the weight of the “shells” is great too!
I made a base from balsa wood, and painted and weathered the base too. Made two beams also of balsa to place in the front and rear of the mortar’s carriage. Everything is movable, the mortar’s carriage just sits on the base and I then slide the beams on each end. Could use the base for other dios.
ABSOLUMENT MAGNIFIQUE !!! 
Très fort !
