For those interested, here are some additional photos showing more detail;
This photo shows the detail of the ball bearing handle on the center rod which rotates as you draw the carriage back due to the action of the rack and pinion.
This next photo shows the detail of rack and pinion inside of the carriage. The pinion gear is fixed to the center rod so as the rack moves upward (as the carriage is drawn back)it turns the rod, which is in turn threaded into the rifling rod/cutter assembly.
This photo is a close up of the inboard indexing chuck. The spindle turns inside a bronze bush pressed into the aluminum plate. On the back is a large knurled nut to clamp it into a stationary position. A pin is visible at the 9:00 position to locate the holes during indexing. Holes are drilled in this indexing plate to allow divisions of 2, 3, 4, 5, 6, 7, 8, 10, 12, 15, & 32 for a corresponding number of grooves in the barrel.
This is the outboard chuck. It is basicly the same as the inboard chuck except their is no indexing plate. This chuck is a close fit in the bush and is free turning for to allow indexing the barrel (from the other end).
This is a view of the carriage from the left side of the machine. Their is plenty of grease visible on these components to accomplish smooth movement and eliminate any binding. The two screws with locknuts are for gib adjustment on the rack.
This final picture shows some detail of the inboard end piece mount and sine bar anchor. The outboard endpiece mount is identical.
Hope these photos are descriptive and interesting. Cheers!
Perk in Cincinnati