Hi-

It's not clear to me what part is jacketed. The breech?

How is it that you believe the original carriage survived? It certainly appears unusual and similar to what one would have for the Woodruff gun.

Since I've not seen anything published of detailed specs on this piece, I suggest that you consider taking some simple measurements and perhaps write an article to document the piece and its carriage.

Is that a bolted on trunnion band?

I wonder what the ammunition capacity would be? Fixed ammunition, two or three deep in trays?

Among the data:
Total empty weight of the carriage and gun
Actual bore diameter
Bore length
Lenght from rear of base ring to the face of the muzzle
Length of the cascable (handgrip ring or breech handle) to base ring
Trunnion diameter
Trunnion length
Distance between trunnion bases
Diameter of chase
Diameter of muzzle band
Diameter at the reinforce
Height (diameter) of wheels
Track of wheels
What is the maximum angular elevation that the carriage's elevating screw would allow? Minimum?
Diameter of the trail
Diameter of the axle body
Is the axle itself iron (like the Woodruff was supposed to be) or wood?
Height of trunnion axis above ground
Distance from front of wheels to end of trail
Width of cheeks
Weight of an ammunition chest
Dimensions of ammunition chest