The barrels are made from solid brass and are about 6" long and turned on the manual lathe. (at least half of the fun)
Trunnion caps are milled on the CNC from solid brass.
Wheels, Trail, Wheel Spacers are all from Polycarbonate and cut on the CNC.
4-40 threaded rod made from 2.5" long screws were cut to length.
Nuts were 4-40 plated but then milled down to a more scale size and then tumbled to remove the plating.
Two methods were used for drilling the trunnion holes in the barrels. One uses a tapered jig that can be held in the milling vise.
The second method uses an arbor that is held in the bore with loctite for drilling.
These were drilled only 3" deep and do not have a touch hole.....Don't ever plan on firing them!
Two of them are going to ROTC Cadre at Creighton University.
I always wanted to build some of these!